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Cited by 66Reproductive Health and TechnologiesAssisted Reproductive Technology and Twin PregnancyReproductive Health and Contraception

Preconception lifestyle advice for people with infertility

Open access
Boedt, Tessy, Vanhove, Anne-Catherine, Vercoe, Melissa A, Matthys, Christophe, Dancet, Eline, Lie Fong, Sharon·2021·Cochrane Database of Systematic Reviews
DOI 10.1002/14651858.cd008189.pub3PMC PMC8092458
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Abstract

BACKGROUND: Infertility is a prevalent problem that has significant consequences for individuals, families, and the community. Modifiable lifestyle factors may affect the chance of people with infertility having a baby. However, no guideline is available about what preconception advice should be offered. It is important to determine what preconception advice should be given to people with infertility and to evaluate whether this advice helps them make positive behavioural changes to improve their lifestyle and their chances of conceiving. OBJECTIVES: To assess the safety and effectiveness of preconception lifestyle advice on fertility outcomes and lifestyle behavioural changes for people with infertility. SEARCH METHODS: We searched the Cochrane Gynaecology and Fertility Group Specialised Register of controlled trials, CENTRAL, MEDLINE, Embase, PsycINFO, AMED, CINAHL, trial registers, Google Scholar, and Epistemonikos in January 2021; we checked references and contacted field experts to identify additional studies. SELECTION CRITERIA: We included randomised controlled trials (RCTs), randomised cross-over studies, and cluster-randomised studies that compared at least one form of preconception lifestyle advice with routine care or attention control for people with infertility. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures recommended by Cochrane. Primary effectiveness outcomes were live birth and ongoing pregnancy. Primary safety outcomes were adverse events and miscarriage. Secondary outcomes included reported behavioural changes in lifestyle, birth weight, gestational age, clinical pregnancy, time to pregnancy, quality of life, and male factor infertility outcomes. We assessed the overall quality of evidence using GRADE criteria. MAIN RESULTS: We included in the review seven RCTs involving 2130 participants. Only one RCT included male partners. Three studies compared preconception lifestyle advice on a combination of topics with routine care or attention control. Four studies compared preconception lifestyle advice on one topic (weight, alcohol intake, or smoking) with routine care for women with infertility and specific lifestyle characteristics. The evidence was of low to very low-quality. The main limitations of the included studies were serious risk of bias due to lack of blinding, serious imprecision, and poor reporting of outcome measures. Preconception lifestyle advice on a combination of topics versus routine care or attention control Preconception lifestyle advice on a combination of topics may result in little to no difference in the number of live births (risk ratio (RR) 0.93, 95% confidence interval (CI) 0.79 to 1.10; 1 RCT, 626 participants), but the quality of evidence was low. No studies reported on adverse events or miscarriage. Due to very low-quality evidence, we are uncertain whether preconception lifestyle advice on a combination of topics affects lifestyle behavioural changes: body mass index (BMI) (mean difference (MD) -1.06 kg/m², 95% CI -2.33 to 0.21; 1 RCT, 180 participants), vegetable intake (MD 12.50 grams/d, 95% CI -8.43 to 33.43; 1 RCT, 264 participants), alcohol abstinence in men (RR 1.08, 95% CI 0.74 to 1.58; 1 RCT, 210 participants), or smoking cessation in men (RR 1.01, 95% CI 0.91 to 1.12; 1 RCT, 212 participants). Preconception lifestyle advice on a combination of topics may result in little to no difference in the number of women with adequate folic acid supplement use (RR 0.98, 95% CI 0.95 to 1.01; 2 RCTs, 850 participants; I² = 4%), alcohol abstinence (RR 1.07, 95% CI 0.99 to 1.17; 1 RCT, 607 participants), and smoking cessation (RR 1.01, 95% CI 0.98 to 1.04; 1 RCT, 606 participants), on low quality evidence. No studies reported on other behavioural changes. Preconception lifestyle advice on weight versus routine care Studies on preconception lifestyle advice on weight were identified only in women with infertility and obesity. Compared to routine care, we are uncertain whether preconception lifestyle advice on weight affects the number of live births (RR 0.94, 95% CI 0.62 to 1.43; 2 RCTs, 707 participants; I² = 68%; very low-quality evidence), adverse events including gestational diabetes (RR 0.78, 95% CI 0.48 to 1.26; 1 RCT, 317 participants; very low-quality evidence), hypertension (RR 1.07, 95% CI 0.66 to 1.75; 1 RCT, 317 participants; very low-quality evidence), or miscarriage (RR 1.50, 95% CI 0.95 to 2.37; 1 RCT, 577 participants; very low-quality evidence). Regarding lifestyle behavioural changes for women with infertility and obesity, preconception lifestyle advice on weight may slightly reduce BMI (MD -1.30 kg/m², 95% CI -1.58 to -1.02; 1 RCT, 574 participants; low-quality evidence). Due to very low-quality evidence, we are uncertain whether preconception lifestyle advice affects the percentage of weight loss, vegetable and fruit intake, alcohol abstinence, or physical activity. No studies reported on other behavioural changes. Precon

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Crossref · 10.1002/14651858.cd008189.pub3

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Claims the paper makes

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  • Findingown data
    § Abstract

    It is uncertain whether preconception lifestyle advice on weight affects gestational diabetes (RR 0.78, 95% CI 0.48 to 1.26; 1 RCT, 317 participants; very low-quality evidence).

    “adverse events including gestational diabetes (RR 0.78, 95% CI 0.48 to 1.26; 1 RCT, 317 participants; very low-quality evidence)”
    Quote in the paperSubstantial claim
  • Findingown data
    § Abstract

    It is uncertain whether preconception lifestyle advice on weight affects hypertension (RR 1.07, 95% CI 0.66 to 1.75; 1 RCT, 317 participants; very low-quality evidence).

    “hypertension (RR 1.07, 95% CI 0.66 to 1.75; 1 RCT, 317 participants; very low-quality evidence)”
    Quote in the paperSubstantial claim
  • Findingown data
    § Abstract

    It is uncertain whether preconception lifestyle advice on alcohol intake affects miscarriages (RR 1.31, 95% CI 0.21 to 8.34; 1 RCT, 37 participants; very low-quality evidence).

    “miscarriages (RR 1.31, 95% CI 0.21 to 8.34; 1 RCT, 37 participants; very low-quality evidence)”
    Quote in the paperSubstantial claim
  • Findingown data
    § Participants

    The included studies were heterogeneous with respect to participants.

    “Studies were heterogeneous with respect to participants.”
    Quote in the paperNot a substantial claim
  • Findingown data
    § Abstract

    Due to very low-quality evidence, it is uncertain whether preconception lifestyle advice on weight affects the percentage of weight loss.

    “Due to very low-quality evidence, we are uncertain whether preconception lifestyle advice affects the percentage of weight loss, vegetable and fruit intake, alcohol abstinence, or physical activity.”
    Quote in the paperSubstantial claim
  • The quote only partly states this claim. 5
  • Classified as probably not a substantial claim. 95
  • May combine two claims. 57

  • The quote only partly states this claim.

    Findingown data
    § Abstract

    No studies reported other behavioural changes for weight advice.

    “No studies reported on other behavioural changes.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data
    § Participants

    Six included studies focused solely on women.

    “The other six studies focused solely on women ( Alibeigi 2020, Belan 2019, Hughes 2000, Mutsaerts 2016, Ng 2018, Rossi 2013).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data
    § Abstract

    One study reported behavioural changes for smoking but not as defined in the review methods.

    “One study reported on behavioural changes for smoking but not as defined in the review methods.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Participants

    One included study enrolled women together with their male partner as a couple, and no included study focused on men only.

    “In one study, women were included with their male partner (i.e., as a couple) (Oostingh 2020); no studies focused on men only.”
    Quote in the paperNot a substantial claim

  • May combine two claims. The quote only partly states this claim.

    Findingown data
    § Abstract

    No studies reported live birth, ongoing pregnancy, adverse events, or miscarriage for smoking advice.

    “No studies reported on live birth, ongoing pregnancy, adverse events, or miscarriage.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data
    § Study design and setting

    The review included seven parallel-design randomised controlled trials with 2130 participants in total.

    “We included seven parallel-design RCTs with a total of 2130 participants, including Hughes 2000, which was the only included study in the 2010 version of this systematic review (Anderson 2010).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Anderson 2010 source

      Not checked in the free run.

  • May combine two claims.

    Findingown data
    § Abstract

    No studies reported adverse events or other behavioural changes for alcohol advice.

    “No studies reported on adverse events or other behavioural changes.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Interventions

    Three included studies assessed preconception lifestyle advice on a combination of topics, and four assessed advice on a single topic.

    “Three studies assessed preconception lifestyle advice on a combination of topics (Alibeigi 2020, Ng 2018, Oostingh 2020); the remaining four studies assessed preconception lifestyle advice on one topic: weight (Belan 2019, Mutsaerts 2016), alcohol intake (Rossi 2013), or smoking (Hughes 2000).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingnone given
    § Abstract

    One study reported behavioural changes for alcohol consumption but not as defined in the review methods.

    “One study reported on behavioural changes for alcohol consumption but not as defined in the review methods.”
    Quote in the paperNot a substantial claim

  • The quote only partly states this claim.

    Findingown data
    § Abstract

    No studies reported other behavioural changes for combination advice.

    “No studies reported on other behavioural changes.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data
    § Outcomes

    Three studies reported on maintaining a healthy weight.

    “For secondary outcome parameters on lifestyle behavioural changes, three studies reported on maintaining a healthy weight (Alibeigi 2020, Belan 2019, Mutsaerts 2016).”
    Quote in the paperNot a substantial claim

  • The quote only partly states this claim.

    Findingown data
    § Primary safety outcomes

    No studies reported miscarriage for the combination comparison.

    “Miscarriage: No studies reported on miscarriage.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data
    § Outcomes

    Four studies reported on following a healthy diet.

    “Four studies reported on following a healthy diet (Belan 2019, Mutsaerts 2016, Ng 2018, Oostingh 2020).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Summary of main results

    The review found seven randomized controlled trials comparing preconception lifestyle advice with routine care or attention control, including 2130 women and men with infertility.

    “We found seven randomized controlled trials (RCTs) comparing preconception lifestyle advice with routine care or attention control in a total of 2130 women and men with infertility.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data
    § Outcomes

    Two studies reported adverse events including gestational diabetes and hypertension, and two studies reported miscarriage.

    “For the primary safety outcomes, two studies reported on adverse events including gestational diabetes and hypertension (Belan 2019, Mutsaerts 2016), and two studies reported on miscarriage.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Gestational age: No studies reported on gestational age.

    Considerable statistical heterogeneity (P = 0.0003, I2 = 92%) and clinical heterogeneity were present between the two studies reporting clinical pregnancy for preconception lifestyle advice on a combination of topics.

    “Considerable statistical heterogeneity (P = 0.0003 and I2 = 92%) and clinical heterogeneity between intervention and comparison were evident.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data
    § Outcomes

    Two studies reported on stopping smoking and other substance abuse.

    “Two studies reported on stopping smoking and other substance abuse.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim. May combine two claims.

    Findingown data
    § Outcomes

    Three studies reported live birth in the study publication, and one study provided live birth data on request.

    “With respect to primary effectiveness outcomes, three studies reported on live birth in the study publication (Belan 2019, Mutsaerts 2016, Rossi 2013), and one study reported data on live birth on request (Oostingh 2020).”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data
    § Interventions

    Only Mutsaerts 2016 provided a full reproducible protocol describing how the intervention was built.

    “All studies described their interventions in their publications; only Mutsaerts 2016 provided a full reproducible protocol on how the intervention was built.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). The quote only partly states this claim.

    Findingown data
    § Primary safety outcomes

    No studies reported adverse events for the combination comparison.

    “Any adverse event: No studies reported on adverse events.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingcitation
    § Interventions

    One study provided preconception lifestyle advice on smoking cessation.

    “One study provided preconception lifestyle advice on smoking cessation (Hughes 2000).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Interventions

    All included studies defined preconception lifestyle advice as the intervention, while control groups received routine care or attention control.

    “All studies defined preconception lifestyle advice as the intervention, whereas the control group received routine care or attention control.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Selective reporting

    Live birth or ongoing pregnancy was reported in three studies, and one study provided live birth data on request.

    “Live birth or ongoing pregnancy was reported in three studies (Belan 2019, Mutsaerts 2016, Rossi 2013), and one study provided data on live birth on request (Oostingh 2020).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Overall completeness and applicability of evidence

    Seven studies met the inclusion criteria for this review, only three of which reported on live birth or ongoing pregnancy (Belan 2019, Mutsaerts 2016, Rossi 2013), and one provided data on live birth on request (Oostingh 2020).

    “Seven studies met the inclusion criteria for this review, only three of which reported on live birth or ongoing pregnancy (Belan 2019, Mutsaerts 2016, Rossi 2013), and one provided data on live birth on request (Oostingh 2020).”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites Belan 2019

      Not checked in the free run.

    • cites Mutsaerts 2016 source

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    • cites Rossi 2013 source

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  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingcitation
    § Interventions

    One study provided preconception lifestyle advice on alcohol intake.

    “One study provided preconception lifestyle advice on alcohol intake (Rossi 2013).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingcitation
    § Secondary outcomes

    Hughes 2000 reported a mean delta stage of change of 0.31 for the experimental group and 0.26 for the control group.

    “The mean delta stage of change was 0.31 for the experimental group and 0.26 for the control group.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Hughes 2000 source

      Not checked in the free run.

  • May combine two claims.

    Findingreasoning
    § Overall completeness and applicability of evidence

    Given the limited number of identified studies, subgroup analyses on participant or intervention characteristics were not feasible, and inclusion of a wide range of participants and interventions resulted in clinical heterogeneity.

    “Given the limited number of identified studies, subgroup analyses on participant or intervention characteristics were not feasible, and inclusion of such a wide range of participants and interventions resulted in clinical heterogeneity.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingnone given
    § Overall completeness and applicability of evidence

    Although lifestyle behavioural changes after the intervention were reported in all studies, a variety of measures and definitions were used to report these changes.

    “Although lifestyle behavioural changes after the intervention were reported in all studies, a variety of measures and definitions were used to report these changes.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingcitation
    § Agreements and disagreements with other studies or reviews

    The review identified one other systematic review on the effects of preconception lifestyle interventions on people with infertility (Lan 2017).

    “We identified one other systematic review on the effects of preconception lifestyle interventions on people with infertility (Lan 2017).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Lan 2017 source

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Findingcitation
    § Agreements and disagreements with other studies or reviews

    In the first edition of this Cochrane review, the need for further research was highlighted because no available RCTs had assessed the effects of preconception advice on live birth or other fertility outcomes in people with diagnosed infertility.

    “In the first edition of this Cochrane systematic review, the need for further research into this subject was highlighted, as no available RCTs had assessed the effects of preconception advice on the chance of live birth or other fertility outcomes in people with diagnosed infertility (Anderson 2010).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Anderson 2010 source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingnone given
    § Additional information

    The Background and Methods were updated to meet current Cochrane standards.

    “Background and Methods updated to meet current Cochrane standards”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data
    § Data and analyses

    In Rossi 2013, the decrease in number of weeks drinking above the safety daily limit in the past 6 months was greater in the experimental group than control, with a mean difference of 3.90 (95% CI -0.76 to 8.56).

    “Decrease in number of weeks drinking above the safety daily limit in the past 6 months (mean ± SD) 5.6 ± 9 in experimental group (n = 16) 1.7 ± 3.5 in control group (n = 21) MD 3.90, 95% CI -0.76 to 8.56”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Rossi 2013 source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingcitation
    § Data and analyses

    In Rossi 2013, the decrease in number of binges in the past 6 months was greater in the experimental group than control, with a mean difference of 13.30 (95% CI -8.54 to 35.14).

    “Decrease in number of binges in the past 6 months (mean ± SD) 14.5 ± 44.4 in experimental group (n = 16) 1.2 ± 4.5 in control group (n = 21) MD 13.30, 95% CI -8.54 to 35.14”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Rossi 2013 source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data
    § Additional information

    The 2021 update identified six additional studies (Alibeigi 2020, Belan 2019, Mutsaerts 2016, Ng 2018, Oostingh 2020, and Rossi 2013) compared with the first version of the review.

    “We identified 6 studies in addition to the first version of this review (Alibeigi 2020 Belan 2019 Mutsaerts 2016 Ng 2018 Oostingh 2020 Rossi 2013)”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingnone given
    § Additional information

    The conclusions of the review changed in the 2021 update.

    “New citation required and conclusions have changed”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingcitation
    § Data and analyses

    In Hughes 2000, the mean delta stage-of-change (difference in stage of motivation to change smoking behaviour) was 0.31 in the experimental group and 0.26 in the control group.

    “Hughes 2000 Delta stage-of-change = difference in stage of motivation to change smoking behaviour (mean) Experimental group (mean): 0.31 (no SD reported) (n = 47) Control group (mean): 0.26 (no SD reported) (n = 47)”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Hughes 2000 source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data
    § Additional information

    The total number of records found in the search was 668.

    “The total number of records found: 668”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data
    § Additional information

    The searches and results were updated in the 2021 update.

    “Searches and results updated.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingnone given
    § Additional information

    A new search was performed on 18 February 2019.

    “18 February 2019 New search has been performed”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingcitation
    § Data and analyses

    In Hughes 2000, the rate of maintained cessation rose from 4% to 24% (P < 0.001), with experimental and control groups reported together.

    “Rate of maintained cessation rose from 4% to 24% (P < 0.001)”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Hughes 2000 source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation
    § Diet

    Diets rich in vegetables, fruits, whole grains, fish, and poultry are linked to better fertility and higher live birth rates in women and improved semen quality in men, while unhealthy diets may have the opposite associations.

    “Evidence suggests that adherence to a diet rich in vegetables, fruits, whole grains, fish, and poultry is related to better fertility and higher live birth rates among women and improved semen quality in men, and unhealthy diets may have the opposite effect (Chiu 2018, Gaskins 2018a, Giahi 2016, Grieger 2018, Salas-Huetos 2017, Vujkovic 2010).”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites Chiu 2018 source

      Not checked in the free run.

    • cites Gaskins 2018a

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    • cites Giahi 2016 source

      Not checked in the free run.

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    Premisecitation
    § Diet

    Some foods may carry salmonella, toxoplasmosis, campylobacter, or listeria, which can cause infection and adverse pregnancy outcomes.

    “These food items may contain salmonella, toxoplasmosis, campylobacter, or listeria, which may cause infection and consequently adverse pregnancy outcomes.”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Government of South Australia 2015

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    • cites Ross 2006

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  • Classified as probably not a substantial claim.

    Premisecitation
    § Description of the intervention

    Lifestyle modification is the first-line treatment for obesity in women and men.

    “Therefore, lifestyle modification is first-line treatment for women and men with obesity (Best 2017, Practice Committee 2015).”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites Best 2017 source

      Not checked in the free run.

    • cites Practice Committee 2015

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  • May combine two claims.

    Premisecitation
    § Diet

    Iron supplementation can prevent maternal anaemia and improve birth outcomes such as birth weight.

    “Iron supplementation can prevent maternal anaemia and improve birth outcomes including birth weight (Haider 2017, World Health Organization 2012).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Haider 2017 source

      Not checked in the free run.

    • cites World Health Organization 2012

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  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data
    § Assessment of risk of bias in included studies

    Three review authors independently assessed included studies for risk of bias using the Cochrane 'Risk of bias' tool.

    “Three review authors (TB, ACV, MV) independently reviewed the included studies for risk of bias using the Cochrane 'Risk of bias' assessment tool”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data
    § Participants

    In Alibeigi 2020, women in the intervention group had more previous IVF attempts than women in the control group (P = 0.029).

    “women in the intervention group had a greater number of previous IVF attempts than women in the control group (P = 0.029)”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductcitation
    § Participants

    In Mutsaerts 2016, median duration of time trying to conceive was longer in the intervention group than in the control group (P = 0.037).

    “Median duration of time trying to conceive was longer in the intervention group than in the control group in Mutsaerts 2016 (P = 0.037);”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data
    § Data extraction and management

    Three review authors independently extracted data from eligible studies using a data extraction form.

    “Three review authors (TB, ACV, MV) independently extracted data from eligible studies using a data extraction form”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data
    § Participants

    In Alibeigi 2020, women in the intervention group were more highly educated than women in the control group (P = 0.004).

    “and women in the intervention group were more highly educated than control group women (P = 0.004).”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Interpretationreasoning
    § Abstract

    This review does not provide clear guidance for clinical practice in this area.

    “This review does not provide clear guidance for clinical practice in this area.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given
    § Dealing with missing data

    Data were analysed on an intention-to-treat basis as far as possible.

    “We analysed the data on an intention-to-treat basis as far as possible”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S1 (asserted), S3 (load-bearing). May combine two claims.

    Study design and conductreasoning
    § Assessment of reporting biases

    The review aimed to minimise publication bias by ensuring a comprehensive search and being alert to duplicate data.

    “we aimed to minimise their potential impact by ensuring a comprehensive search for eligible studies and by being alert for duplication of data”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationreasoning
    § Abstract

    Evidence was insufficient to allow conclusions on the effects of preconception lifestyle advice on adverse events, miscarriage, and safety.

    “Evidence was insufficient to allow conclusions on the effects of preconception lifestyle advice on adverse events and miscarriage and on safety”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Study design and conductown data
    § Participants

    At baseline, intervention and control groups were comparable except in Alibeigi 2020, Mutsaerts 2016, and Rossi 2013.

    “At baseline, participants in the intervention and control groups were comparable, with the exception of Alibeigi 2020: women in the intervention group had a greater number of previous IVF attempts than women in the control group (P = 0.029); and women in the intervention group were more highly educated than control group women (P = 0.004).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation
    § Other substance use

    Non-prescription and recreational drug use during pregnancy is associated with higher risks of foetal death, low birth weight, and preterm birth.

    “However, current data suggest that non-prescription and recreational drug use during pregnancy is associated with increased risk of foetal death, low birth weight, and preterm birth (Gouin 2011, Gunn 2016Ladhani 2011, Metz 2017).”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites Gouin 2011 source

      Not checked in the free run.

    • cites Gunn 2016Ladhani 2011

      Not checked in the free run.

    • cites Metz 2017 source

      Not checked in the free run.

  • May combine two claims.

    Study design and conductown data
    § Quality of the evidence:

    The main limitations of the evidence were poor study methods (lack of blinding) and lack of precision in findings for live birth, safety outcomes, and reported behavioural changes.

    “The main limitations of the evidence were poor study methods in included studies (lack of blinding) and lack of (precision in) findings for live birth, safety outcomes, and reported behavioural changes.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data
    § Selection of studies

    Three review authors independently screened titles and abstracts for potentially relevant studies.

    “Three review authors (TB, ACV, MV) independently performed an initial screen of titles and abstracts retrieved by the search for potentially relevant studies.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductown data
    § Participants

    In Rossi 2013, the intervention group had on average 2.1 drinks per drinking day and the control group had 1.8.

    “in Rossi 2013 the intervention group had on average 2.1 drinks/drinking per day and the control group 1.8.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation
    § Smoking

    Active and passive tobacco smoking is associated with lower fertility and reduced chance of a healthy live birth in the general population and in couples with infertility.

    “Analysis of the literature indicates that active and passive (second-hand) smoking of tobacco is associated with decreased fertility and reduced chance of a healthy, live birth both in the general population and among couples with infertility (Augood 1998, Hyland 2016, Practice Committee 2018, Radin 2014, Sharma 2016, Waylen 2008).”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites Augood 1998 source

      Not checked in the free run.

    • cites Hyland 2016

      Not checked in the free run.

    • cites Practice Committee 2018

      Not checked in the free run.

  • May combine two claims.

    Premisecitation
    § Why it is important to do this review

    Fertility clinics have seen increasing numbers of patients with unhealthy lifestyles and have increasingly recognised the importance of preconception lifestyle advice.

    “Over past years, fertility clinics have tended to see an increasing number of patients with an unhealthy lifestyle, and they have acknowledged more and more the importance of providing preconception lifestyle advice (Gormack 2015, Homan 2018).”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites Gormack 2015 source

      Not checked in the free run.

    • cites Homan 2018 source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation
    § Why it is important to do this review

    ESHRE guidelines on routine psychosocial care in infertility and medically assisted reproduction reflect the importance of preconception lifestyle advice.

    “The importance of providing preconception lifestyle advice is also reflected in the guidelines on routine psychosocial care in infertility and medically assisted reproduction of the European Society of Human Reproduction and Embryology (ESHRE) (ESHRE guideline 2015).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites ESHRE guideline 2015

      Not checked in the free run.

  • May combine two claims.

    Study design and conductown data
    § Selective reporting

    The study details of Hughes 2000 could not be verified because no protocol was available and the study was not prospectively registered.

    “The study details of Hughes 2000 could not be verified, as no study protocol was available and the study was not prospectively registered.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning
    § Incomplete outcome data

    Two studies were rated at unclear risk of attrition bias because missing outcome data were not described.

    “We therefore rated these studies at unclear risk of attrition bias at this point.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Study design and conductown data
    § Selective reporting

    Protocols were available for six studies, and four were prospectively registered.

    “Protocols were available for six studies (Alibeigi 2020, Belan 2019, Mutsaerts 2016, Ng 2018, Oostingh 2020, Rossi 2013); four were prospectively registered (Alibeigi 2020, Belan 2019, Mutsaerts 2016, Oostingh 2020).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data
    § Other potential sources of bias

    Oostingh 2020 was rated at unclear risk of other bias because it was unclear which lifestyle questionnaire was used and whether it had been validated.

    “Another study was rated at unclear risk of other bias, as it was not clear which lifestyle questionnaire was used, and if this questionnaire had been validated (Oostingh 2020).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Study design and conductown data
    § Selective reporting

    Rossi 2013 was not prospectively registered, did not report quality of life, and had missing baseline alcohol intake data.

    “Finally, Rossi 2013 was not prospectively registered.Although these study authors did report on live birth, they did not report on quality of life (a pre-specified outcome), and baseline data on alcohol intake were missing (Rossi 2013).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given
    § Selective reporting

    The review considered studies to be at low risk of reporting bias if a protocol was prospectively registered and live birth or ongoing pregnancy was included as an outcome.

    “We considered studies to be at low risk of reporting bias if a protocol was prospectively registered and live birth or ongoing pregnancy was included as an outcome measure.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Study design and conductreasoning
    § Blinding of outcome assessors (detection bias)

    The review considered that not blinding outcome assessors was unlikely to influence primary review outcomes and certain secondary outcomes.

    “We considered that not blinding outcome assessors was unlikely to influence the primary review outcomes (live birth, ongoing pregnancy, adverse events, and miscarriage) and certain secondary outcomes, including birth weight, gestational age, clinical pregnancy, and time to pregnancy.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data
    § Sequence generation

    One study was rated at unclear risk of selection bias for sequence generation.

    “One study was rated at unclear risk of selection bias of sequence generation (Alibeigi 2020).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Study design and conductown data
    § Incomplete outcome data

    Alibeigi 2020 was rated at low risk of attrition bias because missing data and discontinuation were documented and balanced, and all randomised women were included in the intention-to-treat analysis.

    “In Alibeigi 2020, missing data and reasons for discontinuation were documented and were balanced between groups (five in the intervention group, six in the control group), and all randomized women were included in the ITT analysis.This study was rated at low risk of attrition bias.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Study design and conductown data
    § Selective reporting

    Alibeigi 2020 had a prospectively registered protocol but did not report live birth or ongoing pregnancy, and dietary behaviour data were measured but not reported.

    “Alibeigi 2020 had a prospectively registered protocol but did not report on live birth or ongoing pregnancy.In addition, data on dietary behaviour were measured but were not reported.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Study design and conductown data
    § Selective reporting

    Oostingh 2020 had an unreported pre-specified outcome and reported an outcome not specified in the protocol.

    “Oostingh 2020 had an unreported pre-specified outcome (Big 3 complications including smallfor-gestational-age, premature birth, and congenital malformations and reported an outcome (lifestyle risk score) not specified in the protocol.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning
    § Allocation concealment

    Two studies were rated at unclear risk of selection bias for allocation concealment.

    “These two studies were rated at unclear risk of this bias (Alibeigi 2020, Rossi 2013).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductown data
    § Chapter 2: Systematic review on lifestyle interventions and infertility

    In Rossi 2013, no sample size calculation was reported; the study was a sub-analysis of a larger trial.

    “Sample size calculation: no, sub-analyses of larger trial”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Study design and conductreasoning
    § 

    The Belan 2019 trial was judged at high risk of bias for blinding of outcome assessors for patient-reported outcomes because the outcome assessor was the unblinded participant and reported behavioural changes are likely to be influenced.

    “outcome assessor is participant and is not blinded; reported behavioural changes are likely to be influenced.Eating healthy and moving is socially desirable”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim. May combine two claims.

    Premisecitation
    § Quality of the evidence

    Failure to report live birth in infertility trials is a major source of bias, as it should be the default primary outcome in such studies.

    “Failure to report live birth in infertility trials is a major source of bias, as it should be the default primary outcome in such studies (Harbin Consensus Conference Workshop Group 2014).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Harbin Consensus Conference Workshop Group 2014 source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductown data
    § 

    The Mutsaerts 2016 trial reported a power calculation assuming an increase in vaginal birth of a healthy singleton at term from 45% to 60%, a 20% discontinuation rate, and 5% loss to follow-up, requiring 285 women per group for 80% power at a two-sided alpha of 5%.

    “the power calculations were based on an assumption of an increase in the rate of vaginal birth of a healthy singleton at term from 45% in the control group to 60% in the intervention group, a 20% discontinuation rate during the lifestyle intervention, and a 5% loss to follow-up.We calculated that a sample of 285 women per group would provide the trial with a power of 80% at a two sided alpha level”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data
    § Study duration: June 2016 to August 2019

    In NG 2018, incomplete outcome data was at unclear risk of bias.

    “only abstract with limited data is available as of February 2021, so risk of attrition bias is unclear at this point ITT analysis is planned.400 women are recruited, 236 randomised (131 intervention, 133 control); no further information on missing data is available (yet)”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data
    § 

    The Hughes 2000 trial reported no baseline differences between groups.

    “Baseline differences: no”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Study design and conductreasoning
    § 

    The Belan 2019 trial was judged at high risk of bias for selective outcome reporting because not all pre-specified outcomes were reported and only abstracts with limited data were available.

    “prospectively registered study protocol is available.Not all pre-specified outcomes are reported at this point.Only abstracts with limited data were available as of February 2021, so risk of reporting bias is high at this point”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning
    § Chapter 2: Systematic review on lifestyle interventions and infertility

    In Oostingh 2020, other sources of bias were at unclear risk.

    “Not clear which lifestyle questionnaire was used, and if this questionnaire was validated”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductcitation
    § 

    The Belan 2019 trial reported a sample size calculation based on live birth and the Fertility Fitness Programme, with 58 women per group providing 80% power to detect a doubling in live-birth rates from 25% to 50%, and assuming 10% dropout.

    “based on the outcome of live birth and the Fertility Fitness Programme, the inclusion of 58 women per group provides 80% power to identify a doubling in live-birth rates with this programme (25% to 50%, α=5%).Assuming a dropout rate of 10% the final estimate sample size will be 128 women”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data
    § 

    In the NTR 1530 study, sequence generation was at low risk of bias.

    “randomization was performed online and was stratified according to trial centre and ovulatory status”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductnone given
    § Potential biases in the review process

    The review was conducted according to Cochrane methods, with a pre-defined protocol to minimize potential bias.

    “This review was conducted according to Cochrane methods, with a pre-defined protocol to minimize potential bias.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data
    § 

    The Hughes 2000 trial was judged at unclear risk of bias for blinding of outcome assessors for objective outcomes because there were no objective outcome measures.

    “Not applicable; no objective outcome measures in this study”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Study design and conductreasoning
    § 

    The Hughes 2000 trial was judged at high risk of bias for blinding of outcome assessors for patient-reported outcomes because the outcome assessor was the unblinded participant and reported smoking changes are likely to be influenced.

    “outcome assessor is participant and is not blinded; reported behavioural changes in smoking are likely to be influenced.Having quit smoking is a more desirable answer”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given
    § Potential biases in the review process

    Risk of bias assessment for reporting bias was independently conducted by two review authors.

    “Risk of bias assessment for reporting bias was independently conducted by two review authors.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning
    § Study duration: June 2016 to August 2019

    In NG 2018, other sources of bias were at high risk.

    “only abstracts with interim analyses are available”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Study design and conductnone given
    § Chapter 2: Systematic review on lifestyle interventions and infertility

    In Oostingh 2020, incomplete outcome data was at unclear risk of bias.

    “ITT analysis, but study authors did not impute on ITT those lost to follow-up; we assumed in our analysis that they did not have a clinical pregnancy.Missing data documented but not balanced between groups.30.2% in intervention group vs 18.2% in control group.Reasons for discontinuation not reported”
    Quote in the paperNot a substantial claim
    • The authors state this as an assumption: In the analysis of Oostingh 2020, participants lost to follow-up were assumed not to have had a clinical pregnancy.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning
    § Study duration: June 2016 to August 2019

    In NG 2018, blinding of outcome assessors was at unclear risk of bias because there were no objective outcome measures.

    “Not applicable; no objective outcome measures in this study”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data
    § Chapter 2: Systematic review on lifestyle interventions and infertility

    In Oostingh 2020, sequence generation was at low risk of bias.

    “for each stratum, a permuted block design is used and programmed before-hand”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data
    § Study duration: June 2016 to August 2019

    In NG 2018, sequence generation was at low risk of bias.

    “participating women will be randomised in programme by the computer generation of a series of validation codes which is unique for each participant”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data
    § 

    The Hughes 2000 trial was judged at low risk of bias for sequence generation because a computer-generated, blocked schedule was used.

    “randomised using a computer-generated, blocked schedule”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Study design and conductreasoning
    § Study duration: June 2016 to August 2019

    In NG 2018, selective outcome reporting was at high risk of bias.

    “prospectively registered study protocol is available.Not all pre-specified outcomes are reported at this point.Only abstracts with limited data are available as of February 2021, so risk of reporting bias is high at this point”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data
    § Study duration: June 2016 to August 2019

    In Oostingh 2020, the study author reported no baseline differences between groups.

    “no, study author replied by email that there were no baseline differences be-tween groups”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning
    § Low risk

    In the NTR 1530 study, other sources of bias were at low risk.

    “Study appears free of other sources of bias”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductnone given
    § Potential biases in the review process

    The review aimed to minimize reporting bias by conducting a comprehensive search for eligible studies and by being alert for duplication of data.

    “We aimed to minimize reporting bias by conducting a comprehensive search for eligible studies and by being alert for duplication of data.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductown data
    § Study duration: June 2016 to August 2019

    In NG 2018, the sample size calculation was performed but the target was not achieved; the protocol specified 440 participants but only 264 were randomised.

    “Sample size calculation: yes, but not (yet) achieved: protocol says 440, abstract reported on 264”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Study design and conductown data
    § Potential biases in the review process

    Due to the small number of studies included, the review was not able to construct a funnel plot and consequently could not examine publication bias.

    “Due to the small number of studies included in the review, we were not able to construct a funnel plot, and consequently, we were not able to examine the presence of publication bias.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning
    § 

    In the NTR 1530 study, allocation concealment was at low risk of bias.

    “central randomisation centre”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data
    § 

    The Mutsaerts 2016 trial reported a significant baseline difference between groups in median duration of time attempting to conceive (P = 0.037).

    “Baseline differences: yes, there were significant differences between groups for the median duration of time attempting to conceive (P = 0.037)”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning
    § 

    The Alibeigi 2020 trial was judged at unclear risk of bias for allocation concealment because the method of concealment was not clear.

    “the random allocation sequence was generated by an investigator who was not involved in eliciting data or conducting the study”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data
    § Characteristics of included studies [ordered by study ID]

    The Alibeigi 2020 trial reported a sample size calculation based on a 5% significance level, 80% power, and a 25% between-group difference in one outcome, assuming a 30% baseline success rate.

    “the sample size was calculated using a significance level of 0.05 and a power of 80% to detect at least a difference of 25% between groups in 1 outcome of the study for the baseline success rate of 30%.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data
    § Study duration: June 2016 to August 2019

    In NG 2018, allocation concealment was at low risk of bias.

    “computer generation of a series of validation codes which is unique for each participant.After completion of the baseline questionnaires, women will be randomised to the intervention or the control group.The randomisa tion process will be concealed”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning
    § 

    The Alibeigi 2020 trial was judged at unclear risk of bias for sequence generation because block randomisation was reported but the block selection process was not specified.

    “randomization was stratified according to age groups.According to the order of entrance to the study, based on permuted blocks of size four, the patients in each of the 4 age groups of < 30, 30-34, 35-37, and 38-40 years were randomly assigned to the intervention and control groups”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given
    § Potential biases in the review process

    Reporting bias was assessed through careful assessment of included studies for failure to report obvious outcomes or for reporting them in insufficient detail.

    “Reporting bias was assessed through careful assessment of included studies for failure to report obvious outcomes or for reporting them in insufficient detail.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation
    § Overall completeness and applicability of evidence

    Infertility is a couple's condition, and couples may have a correlated lifestyle, for example, in weight and diet.

    “Infertility is a couple's condition, and couples may have a correlated lifestyle, for example, in weight and diet (Best 2017).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Best 2017 source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning
    § Study duration: June 2016 to August 2019

    In NG 2018, blinding of participants and personnel was at high risk of bias for all outcomes.

    “although clinicians were blinded throughout, due to the nature of the study, it was not possible to blind women who were randomised”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Study design and conductreasoning
    § 

    The Hughes 2000 trial was judged at high risk of bias for selective outcome reporting because no study protocol was available, live birth was not collected, and CO exhalation was tested but not reported.

    “no study protocol was available to further verify selective outcome reporting.Study authors were contacted for the previous version of this systematic review on reporting of live birth.They reported that this information was not collected.this information could have been collected at 12-month follow-up.Secondary outcome (rate of maintained cessation): no data on infertile and pregnant women were”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Study design and conductcitation
    § 

    The Belan 2019 trial reported no statistical or clinical baseline differences between groups for the modified per-protocol analysis.

    “there were no statistical or clinical differences between the intervention and control groups for the mPP analysis”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data
    § 

    In the NTR 1530 study, blinding of participants and personnel was at high risk of bias for all outcomes.

    “blinding was not possible.However, we specified the type of infertility treatment before randomisation in order to minimize differences in treatment assignments; this led to similar distributions of infertility treatment in both groups”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning
    § 

    The Belan 2019 trial was judged at low risk of bias from other sources because only abstracts with limited data were available.

    “only abstracts with limited data are available”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Study design and conductown data
    § 

    The Hughes 2000 trial reported a sample size calculation based on a clinically significant difference in delta stage-of-change of 1.0, with alpha 0.05 and beta 0.20, requiring 107 patients per arm, but the target was not achieved for each independent sample and the study was underpowered.

    “sample size estimation was based on what was considered to be a clinically significant difference between intervention and control in delta stage-of-change of 1.0.Standard assumptions of alpha (2-tailed) = 0.05 and beta = 0.20 were used.The sample required was 107 patients per study arm.Although this target was reached for combined infertile and pregnant participants (N = 214), it was not attained”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Interpretationreasoning
    § Authors' conclusions Implications for practice

    This review does not provide clear guidance for clinical practice on preconception lifestyle advice.

    “This review does not provide clear guidance for clinical practice on preconception lifestyle advice.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning
    § Chapter 2: Systematic review on lifestyle interventions and infertility

    In Oostingh 2020, blinding of outcome assessors was at low risk of bias for objective outcomes.

    “not clear if outcome assessors were blinded.Clinical pregnancy not likely to be influenced, as this is an observer-reported outcome not involving judgement”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductown data
    § Characteristics of included studies [ordered by study ID]

    In the Alibeigi 2020 trial, the intervention and control groups differed at baseline in previous IVF attempts (P = 0.029) and education level (P = 0.004).

    “Baseline differences: yes, differences in in previous IVF attempts (P = 0.029) and differences in education level (P = 0.004) between control and intervention”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationreasoning
    § Authors' conclusions Implications for practice

    The review highlights the lack of evidence on this topic, despite recommendations by international guidelines to provide counselling to all couples with infertility.

    “However, it highlights the lack of evidence on this topic, despite recommendations by international guidelines to provide counselling to all couples with infertility.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim. May combine two claims.

    Interpretationreasoning
    § Potential biases in the review process

    Because interventions in some studies were not initiated as preconception lifestyle advice alone, do not reflect daily clinical practice, and do not allow for assessment of lifestyle behavioural changes, such studies were excluded from the review.

    “Because these interventions were not initiated as preconception lifestyle advice alone, do not reflect daily clinical practice, and do not allow for assessment of lifestyle behavioural changes, we did not include such studies in our review.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given
    § Potential biases in the review process

    No changes were made to the review as a result of the findings of included studies.

    “No changes were made as a result of the findings of included studies.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductreasoning
    § 

    The Alibeigi 2020 trial was judged at unclear risk of bias for blinding of outcome assessors for patient-reported outcomes because assessors were not blinded, though BMI and clinical pregnancy were unlikely to be influenced.

    “outcome assessors were not blinded.BMI and clinical pregnancy were not likely to be influenced, as they are observer-reported outcomes not involving judgement”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data
    § 

    The Belan 2019 trial was judged at unclear risk of bias for incomplete outcome data because only abstracts with limited data were available.

    “only abstracts with limited data were available as of February 2021, so risk of attrition bias is unclear at this point”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Study design and conductown data
    § 

    The Alibeigi 2020 trial was judged at high risk of bias for selective outcome reporting because dietary behaviour and adherence were measured but not reported, and live birth or ongoing pregnancy was not included.

    “prospectively registered study protocol was available.Most out-comes were analysed and reported in accordance with the protocol.Change in dietary behaviour and adherence to intervention were measured but not re-ported.Live birth or ongoing pregnancy was not included”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductown data
    § Study duration: June 2016 to August 2019

    In NG 2018, there were no baseline differences in vegetable intake, fruit intake, or folic acid intake, but no further details on other baseline characteristics were reported.

    “no baseline differences in vegetable intake, fruit intake, or folic acid intake; no further details on other baseline characteristics”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning
    § Low risk

    In the NTR 1530 study, selective outcome reporting was at low risk of bias.

    “prospectively registered study protocol was available; outcomes were analysed and were reported in accordance with the protocol.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductreasoning
    § 

    The Alibeigi 2020 trial was judged at low risk of bias for incomplete outcome data because an intention-to-treat analysis was used and missing data were balanced.

    “the study flowchart for IVF is shown in Figure 1.Five women in the intervention group and 6 women in the control group were excluded due to lack of willingness and cooperation.Their data were used to assess the outcome of spontaneous pregnancy, but spontaneous pregnancies did not occur to them”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductown data
    § Study duration: June 2016 to August 2019

    In Oostingh 2020, the sample size calculation was performed but the target was not achieved; the protocol aimed for 1000 fertile and 1000 subfertile women, but only 848 participants were randomised.

    “Sample size calculation: yes, but not achieved.Aimed for 3000 (general preconception cohort + sub-fertile cohort) in trial register.Aimed for 1000 general and 1000 subfertile in protocol”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning
    § 

    The Alibeigi 2020 trial was judged at low risk of bias for blinding of outcome assessors for objective outcomes because all outcomes were objective and quantitative clinical tests.

    “however, all outcomes were measured based on clinical tests.They were all objective and quantitative not qualitative, so they could not be biased”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data
    § Additional information

    In Chang 2011, other sources of bias were judged low risk because the study appeared free of other sources of bias.

    “Other sources of bias Low risk Comment: study appears free of other sources of bias”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Chang 2011 source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given
    § Additional information

    GRADE assessment was performed on the outcomes.

    “GRADE assessment was performed on the outcomes”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductcitation
    § Additional information

    In Chang 2011, incomplete outcome data was judged high risk because 161 out of 511 randomised participants were reported to have infertility, but outcome data were available only for 37 participants.

    “Incomplete outcome data High risk Comment: in Chang 2011 (table 2), 161 out of 511 participants randomised are reported to have infertility.However outcome data are available only for 37 participants.Study authors were contacted twice for clarification, but no reply was received as of February 2021”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Chang 2011 source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning
    § Additional information

    In Chang 2011, blinding of outcome assessors for objective outcomes was judged low risk because live birth and miscarriage are observer-reported outcomes not involving judgement.

    “Blinding of outcome as sessors Objective outcomes Low risk Comment: outcome assessors were not blinded.Live birth and miscarriage were not likely to be influenced, as they are observer-reported outcomes not involving judgement”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Chang 2011 source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductcitation
    § Additional information

    In Chang 2011, blinding of participants and personnel was judged high risk because participants and study staff could not be blinded to treatment group assignment.

    “Blinding of participants and personnel All outcomes High risk Quote:”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Chang 2011 source

      Not checked in the free run.

    • cites Saitz et al., 2007

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductreasoning
    § Additional information

    In Chang 2011, blinding of outcome assessors for patient-reported outcomes was judged high risk because the outcome assessor is the participant and is not blinded, and reported behavioural changes regarding drinking are likely to be influenced.

    “Blinding of outcome as sessors Patient reported outcome measures High risk Comment: outcome assessor is participant and is not blinded; reported behavioural changes regarding drinking are likely to be influenced, as less drinking is known to be socially desirable”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Chang 2011 source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductcitation
    § Additional information

    In Chang 2011, sequence generation was judged low risk because a computer-generated random assignment list was used.

    “Sequence generation Low risk Quote:”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Chang 2011 source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data
    § Additional information

    The authors declare no conflicts of interest.

    “TB, ACV, MV, CM, ED, and SLF declare that they do not have any conflicts of interest.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Study design and conductreasoning
    § Additional information

    The review authors used a random-effects model instead of a fixed-effect model because large variation between studies was expected in populations and/or interventions.

    “the review authors agreed to use a random-effects model instead of a fixed-effect model because large variation between studies is expected (in populations and/or interventions)”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given
    § Additional information

    A narrative review summary format was chosen as the method for synthesis when it was not possible to conduct meta-analyses.

    “a narrative review summary format was chosen as the method for synthesis when it was not possible to conduct meta-analyses”
    Quote in the paperNot a substantial claim
137 of 137

  • The paper relies on this without support.

    No guideline exists about what preconception advice should be offered to people with infertility.

    “However, no guideline is available about what preconception advice should be offered.”

  • The paper relies on this without support.

    Weeks 3 to 8 of pregnancy are the most sensitive period for embryo development.

    “More specifically, Weeks 3 to 8 of pregnancy are the most sensitive in development of the embryo.”

  • The paper relies on this without support.

    Non-randomised studies are associated with high risk of bias.

    “We excluded non-randomised studies, as they are associated with high risk of bias.”

  • The authors state this as an assumption.

    For absolute effect calculations, 75% of women abstain from alcohol with routine care or attention control.

    “if it is assumed that 75% of women abstain from alcohol with routine care or attention control”

  • The authors state this as an assumption.

    For absolute effect calculations, 95% of women receiving routine care or attention control achieve smoking cessation.

    “If it is assumed that smoking cessation is seen in 95% of women receiving routine care or attention control”

  • The authors state this as an assumption.

    Participants without a reported outcome were assumed not to have had live birth or ongoing pregnancy.

    “live birth or ongoing pregnancy was assumed not to have occurred in participants without a reported outcome.”

  • The authors state this as an assumption.

    In the analysis, dropouts in Mutsaerts 2016 were assumed not to have had a live birth.

    “In our analysis, we assumed that these dropouts did not have a live birth.”

  • The authors state this as an assumption.

    In the analysis, participants lost to follow-up in Oostingh 2020 were assumed not to have had a clinical pregnancy.

    “but we assumed in our analysis that these participants did not have a clinical pregnancy.”

  • The paper relies on this without support.

    Blinding participants to behavioural interventions such as preconception lifestyle advice is difficult.

    “In all studies, participants were aware of the assigned interventions, as it is difficult to blind participants to behavioural interventions such as preconception lifestyle advice.”

  • The authors state this as an assumption.

    In the analysis of the first study, women lost to follow-up or who withdrew consent were assumed not to have had a live birth.

    “we assumed in our analysis that they did not have a live birth.”

  • The authors state this as an assumption.

    In the analysis of Oostingh 2020, participants lost to follow-up were assumed not to have had a clinical pregnancy.

    “we assumed in our analysis that they did not have a clinical pregnancy.”
11 of 11

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • Systematic reviews and prevention campaigns among the diagnosed infertile are effective in reducing intermediate endpoints (weight loss, biomarkers) but not in markedly increasing fertility outcomes such as live births.

    “Systematic reviews and prevention campaigns among the diagnosed infertile (e.g. pre-conception, lifestyle advice) are effective in reducing intermediate endpoints (weight loss, biomarkers) but not in markedly increasing fertility outcomes such as live births (Boedt et al., 2021).”

    From Declining global fertility rates and the implications for family planning and family building: an IFFS consensus document based on a narrative review of the literature (2024) · cites this paper as Boedt et al., 2021

    The Secondary outcomes section (page not provided) says weight-focused advice may slightly reduce BMI in women with infertility and obesity, but the evidence is low quality and its effect on percentage weight loss is uncertain. The Primary effectiveness outcomes section (page not provided) says the effect on live births is also uncertain; the review does not establish that these interventions reliably improve weight loss or biomarkers while failing to increase live births. (LLM, conf=0.88)

    Experimental — accuracy not yet measured

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Miscarriage result is described as a live-birth probability

    Minor

    This passage converts the miscarriage risk ratio into an absolute range but labels that range as the chance of live birth. The outcome being analysed is miscarriage.

  • Ng fruit-intake sample size changes between results and table

    Minor

    The results say the fruit-intake estimate covers 164 women, while the table assigns 131 intervention and 133 control participants to that same estimate, totalling 264.

  • Control-group discontinuation count does not match its breakdown

    Minor

    The listed 61 women and 1 man total 62 control-group discontinuations, not 79.

    Reported 79 · recomputed 62

  • Smoking comparison is labelled as alcohol advice in Table I

    Minor

    The fourth comparison concerns smoking advice and reports smoking outcomes from Hughes 2000, but its Table I heading calls it advice on alcohol intake.

  • Ng trial randomisation total conflicts with its group counts

    Minor

    The stated intervention and control counts sum to 264, not the 236 described as randomised in this passage.

    Reported 236 · recomputed 264

  • Folic-acid dose uses conflicting units

    Minor

    The study characteristics call 400 mg/day adequate folic-acid use, whereas the review defines the measured adequate daily supplement dose as 400 μg. Those doses differ by a factor of 1,000.

6 of 6

Cites

2 retracted

Flagged first, then by citations

7 of the 222 references couldn’t be matched to a known paper.

Research works printed but not linked: 30

  1. Hughes, 1999, A randomised controlled trial of a 'State-of-Change' smoking cessation intervention for subfertile and pregnant patients, Fertility and Sterility, 72, S61
  2. Den Harink, 2019, Preconception lifestyle intervention in obese women improves echocardiographic indices of cardiovascular function in their offspring: follow up of a randomised controlled trial, Cardiology in the Young, 29, S11
  3. Mol, 2015, Effects of preconceptional weight loss on maternal and fetal outcome in obese subfertile women, Journal of Paediatrics and Child Health, 51, 36
  4. Oers, 2016, Is there a different effect of lifestyle intervention in subgroups of infertile obese women? Prespecified subgroup analyses of the LIFEstyle randomized controlled trial, Human Reproduction, 31, 29
  5. Wekker, 2018, Sexual function in obese infertile women 5-6 years after a preconception lifestyle intervention, International Journal of Gynecology and Obstetrics, 143, 402
  6. Wekker, 2017, Effect of a lifestyle intervention in obese infertile women on cardiometabolic health and quality of life: results of a randomised controlled trial, Human Reproduction, 32, i28
  7. Ng, 2019, RCT of the impact of the online lifestyle coaching platform 'Smarter Pregnancy' on modifying peri-conceptual behaviours in women presenting with subfertility or recurrent miscarriages, Human Reproduction, 34, i336
  8. Oostingh, 2018, Improvement of periconception nutrition and lifestyle behaviors using the mHealth program smarter pregnancy: a randomized controlled trial, Reproductive Sciences, 25, 197A
  9. Steegers-Theunissen, 2018, Preconceptional personalised mHealth lifestyle coaching: first results of a randomized controlled trial in couples undergoing IVF/ICSI treatment, Human Reproduction, 33, 75
  10. Ashcroft, 1997, The value of patient education by nurses to improve folate uptake during IVF treatment, Journal of Reproduction and Fertility, 19, 19
  11. Beerendonk, 1996, Anxiety during an IVF procedure the influence of dietary sodium restrictions, several infertility characteristics and early pregnancy, Human Reproduction, 11, 162
  12. Bisht, 2018, Sperm DNA damage: consequences of the impact of yogic cognitive behavior practices, Andrology, 6, 75
  13. Bodin, 2017, The effect of introducing Reproductive Life Plan-based counselling during men's sexual health visits: a randomized controlled trial, Human Reproduction, 32, i395
  14. Clark, 2000, Maximizing weight loss in the overweight infertile patient - a prospective randomized controlled trial, Human Reproduction, 15, 65
  15. Dortaj, 2016, Effectiveness of mindfulness-based cognitive therapy on improvement of stress and infertility in infertile women undergoing IVF, Journal of Reproduction and Infertility, 17, 264
  16. Einarsson, 2017, Weight reduction intervention for obese infertile women prior to IVF: a randomized controlled trial, Human Reproduction, 32, 1621, 10.1093/humrep/dex235 · DOI · Paper page
  17. Emery, 2001, Does counselling prior to IVF affect anxiety and depression scores? Preliminary results of a randomized clinical trial, Human Reproduction, 16, 201
  18. Emery, 2002, What do couples expect and what do the receive through systematic pre-IVF counselling? Results from a randomized controlled study, Human Reproduction, 17, 192
  19. Emery, 2004, Assessing pre-IVF counselling: one-year follow-up, Human Reproduction, 19, i31
  20. Emery, 2006, Prospective study of pre-IVF counselling; one year study follow-up, Journal of Reproductive Medicine and Endocrinology, 1, 77
  21. Jamali, 2016, The effects of education on anxiety levels and sexual satisfaction in infertile women in Iran, Journal of Reproduction and Infertility, 17, 260
  22. Kersten, 2015, Improving the implementation of tailored expectant management in couples with unexplained infertility: results from a cluster randomized controlled trial, Human Reproduction, 30, 57
  23. Overdijkink, 2018, The impact of inadequate maternal nutritional factors on embryo morphokinetic quality after in vitro fertilization or intracytoplasmic sperm injection, Reproductive Sciences, 25, 250A
  24. Sim, 2012, Weight loss improves reproductive outcomes for obese women undergoing assisted reproductive technology, Obesity Facts, 5, 36
  25. Tolahunase, 2017, Yoga and meditation promotes quality of life by decreasing depression severity and cellular aging in male infertility: randomized controlled trial, Andrology, 5, 116
  26. Tolahunase, 2018, Yoga optimized neuroplasticity and regulatory feedback improve semenogram and sperm quality in infertile men with major depressive disorder: a randomized controlled trial, Andrology, 6, 80
  27. Tolahunase, 2018, Impact of yoga- and meditation-based lifestyle intervention on depression and quality of life in infertile couples: a randomized controlled trial, Human Reproduction, 33, 308
  28. Jamebozorg, 2018, The effect of Iranian traditional medicine based dietary intervention on incidence of pregnancy in women undergoing ovulation stimulation, Journal of Reproduction and Infertility, 19, 160
  29. National Institute for Health and Clinical Excellence, 2013, Fertility Problems: Assessment and Treatment (CG156)
  30. World Health Organization, 2010, WHO Laboratory Manual for the Examination and Processing of Human Semen

Cited by

Sorted by citations

Related

Authors
Boedt, T., Vanhove, A.-C., Vercoe, M. A., Matthys, C., Dancet, E., & Lie Fong, S.
Affiliations
  • KU Leuven (BE)
  • Rode Kruis-Vlaanderen (BE)
  • University of Auckland (NZ)
  • Department of Development and Regeneration; KU Leuven; Leuven Belgium
ORCID
Venue
Cochrane Database of Systematic Reviews
Publisher
Wiley
Published
2021-04-29
Volume
2021
Issue
4
Pages
CD008189-CD008189
ISSN
  • 1361-6137 (ISSN-L)
  • 1465-1858
DOI
10.1002/14651858.cd008189.pub3
PMC
PMC8092458
OpenAlex
W3159668067
Cited by
66
References
222
Citations by year
2026: 5 · 2025: 17 · 2024: 15 · 2023: 15 · 2022: 11 · 2021: 3
FWCI
1.80
Type
journal article
Language
en
Open access
Locations
  • Cochrane Database of Systematic Reviews (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
  • Lirias (submittedVersion, other-oa)
Topics
  • Health Sciences › Medicine › Reproductive Medicine › Reproductive Health and Technologies
  • Health Sciences › Medicine › Pediatrics, Perinatology and Child Health › Assisted Reproductive Technology and Twin Pregnancy
  • Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Reproductive Health and Contraception
Keywords
infertility, fertility outcomes, live birth, ongoing pregnancy, miscarriage, behavior change, body weight, alcohol consumption, smoking, male factor infertility, time to pregnancy, quality of life, birth weight, gestational age, clinical pregnancy, guideline development, risk of bias, reporting quality, low- and middle-income countries, cost-effectiveness
MeSH terms
Diet, Healthy, Alcohol Drinking, Central Nervous System Stimulants, Caffeine, Counseling, Female, Folic Acid, Humans, Infertility, Infertility, Female, Life Style, Male, Sex Factors, Vitamin B Complex, Weight Loss, Exercise, Bias, Randomized Controlled Trials as Topic, Smoking Cessation, Preconception Care, Live Birth

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-04.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-04.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

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