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Cited by 168Enhanced Recovery After SurgeryCardiac, Anesthesia and Surgical OutcomesIntensive Care Unit Cognitive Disorders

Relative efficacy of prehabilitation interventions and their components: systematic review with network and component network meta-analyses of randomised controlled trials

Open access
McIsaac, Daniel I, Kidd, Gurlavine, Gillis, Chelsia, Branje, Karina, Al-Bayati, Mariam, Baxi, Adir, Grudzinski, Alexa L, Boland, Laura +3 more·2025·BMJ
DOI 10.1136/bmj-2024-081164PMC PMC11752451
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Abstract

Objective: To estimate the relative efficacy of individual and combinations of prehabilitation components (exercise, nutrition, cognitive, and psychosocial) on critical outcomes of postoperative complications, length of stay, health related quality of life, and physical recovery for adults who have received surgery. Design: Systematic review with network and component network meta-analyses of randomised controlled trials. Data sources: Medline, Embase, PsycINFO, CINAHL, Cochrane Library, and Web of Science were initially searched 1 March 2022, and updated on 25 October 2023. Certainty in findings were assessed using the Confidence in Network Meta-Analysis (CINeMA) approach. Main outcome measures: To compare treatments and to compare individual components informed by partnership with patients, clinicians, researchers, and health system leaders using an integrated knowledge translation framework. Eligible studies were any randomised controlled trial including adults preparing for major surgery who were allocated to prehabilitation interventions or usual care, and where critical outcomes were reported. Results: 186 unique randomised controlled trials with 15 684 participants were included. When comparing treatments using random-effects network meta-analysis, isolated exercise (odds ratio 0.50 (95% confidence interval (CI) 0.39 to 0.64); very low certainty of evidence), isolated nutritional (0.62 (0.50 to 0.77); very low certainty of evidence), and combined exercise, nutrition, plus psychosocial (0.64 (0.45 to 0.92); very low certainty of evidence) prehabilitation were most likely to reduce complications compared with usual care. Combined exercise and psychosocial (−2.44 days (95% CI −3.85 to −1.04); very low certainty of evidence), combined exercise and nutrition (–1.22 days (–2.54 to 0.10); moderate certainty of evidence), isolated exercise (–0.93 days (–1.27 to –0.58); very low certainty of evidence), and isolated nutritional prehabilitation (–0.99 days (–1.49 to –0.48); very low certainty of evidence) were most likely to decrease length of stay. Combined exercise, nutrition, plus psychosocial prehabilitation was most likely to improve health related quality of life (mean difference on Short Form-36 physical component scale 3.48 (95% CI 0.82 to 6.14); very low certainty of evidence) and physical recovery (mean difference in meters on the six min walk test 43.43 (95% CI 5.96 to 80.91); very low certainty of evidence).When comparing individual components using component network meta-analysis, exercise and nutrition were the individual components most likely to improve all critical outcomes. The certainty of evidence for all comparisons across all outcomes was generally low to very low due to trial level risk of bias and imprecision; however, results for exercise and nutritional prehabilitation were robust with exclusion of high risk of bias trials. Conclusions: Consistent and potentially meaningful effect estimates suggest that exercise prehabilitation, nutritional prehabilitation, and multicomponent interventions including exercise may benefit adults preparing for surgery and could be considered in clinical care. However, multicentre trials that are appropriately powered for high priority outcomes and that have a low risk of bias are required to have greater certainty in prehabilitation’s efficacy. Registration: International prospective registry of systematic reviews CRD42023353710.

AI snapshot

Written from the paper’s full text.

TL;DR

In a systematic review with network and component network meta-analyses of 186 randomised controlled trials (15,684 adults preparing for major surgery), exercise, nutrition, and multicomponent exercise-containing prehabilitation were most likely to improve postoperative complications, length of stay, health-related quality of life, and physical recovery. Certainty of evidence was generally low to very low, and the authors conclude that low-risk-of-bias multicentre trials are needed.

Key findings

  • For postoperative complications, isolated exercise (odds ratio 0.50, 95% CI 0.39 to 0.64), isolated nutrition (0.62, 0.50 to 0.77), and combined exercise, nutrition, plus psychosocial prehabilitation (0.64, 0.45 to 0.92) were most likely to reduce complications versus usual care; all very low certainty. Component network meta-analysis found exercise (0.53, 0.42 to 0.66) and nutrition (0.66, 0.54 to 0.81) reduced complications, while psychosocial evidence was consistent with harm (1.75, 1.17 to 2.61).
  • For length of stay, the highest-ranked treatments were exercise plus psychosocial (−2.44 days, 95% CI −3.85 to −1.04; very low certainty), exercise plus nutrition (−1.22 days, −2.54 to 0.10; moderate certainty), isolated nutrition (−0.99 days, −1.49 to −0.48; very low certainty), and isolated exercise (−0.93 days, −1.27 to −0.58; very low certainty). In the interaction component model, exercise (−0.96 days, −1.30 to −0.61) and nutrition (−0.99 days, −1.49 to −0.48) reduced length of stay, but their incremental effects were reduced in the other’s presence.
  • For health-related quality of life, combined exercise, nutrition, plus psychosocial prehabilitation had a mean difference of 3.48 (95% CI 0.82 to 6.14) on the SF-36 physical component score; isolated nutrition was 3.28 (−5.03 to 11.60), and isolated exercise was 2.29 (0.96 to 3.62). In component network meta-analysis, only exercise was statistically significant (2.20, 1.00 to 3.50).
  • For physical recovery, combined exercise, nutrition, plus psychosocial prehabilitation increased six-minute walk test distance by 43.43 m (95% CI 5.96 to 80.91); exercise plus nutrition was 40.52 m (−32.33 to 113.38), isolated psychosocial was 34.50 m (−45.75 to 114.76), and isolated exercise was 25.73 m (6.11 to 45.35). In component network meta-analysis, only exercise was statistically significant (26.25 m, 6.25 to 45.00).

Methods

  • Systematic review with treatment-level random-effects network meta-analysis and component network meta-analysis; searched Medline, Embase, PsycINFO, CINAHL, Cochrane Library, and Web of Science initially on 1 March 2022 and updated on 25 October 2023; registered as CRD42023353710.
  • Included 186 unique randomised controlled trials (n=15,684) of adults >18 years undergoing elective surgery allocated to prehabilitation (exercise, nutrition, cognitive, psychosocial, or multimodal) for seven or more days before surgery versus comparator or usual care, reporting complications, length of stay, health-related quality of life, or physical recovery. Risk of bias was low in 43 trials (23%), moderate in 66 (36%), and high in 77 (41%).
  • Analyses used frequentist random-effects network meta-analysis for treatment comparisons, component network meta-analysis for individual components, CINeMA certainty assessment, P scores for ranking, and sensitivity analyses including exclusion of high-risk-of-bias trials and network meta-regressions.

Limitations

  • The paper states that certainty was low to very low for most analyses, largely due to trial-level risk of bias (especially blinding) and imprecision; heterogeneity within pooled components, sparse data for psychosocial and cognitive prehabilitation, limited representation of these components across surgery types, no consensus on the seven-day prehabilitation threshold, and variation in outcome timing may also limit estimates.
  • The paper states that health-related quality of life and physical recovery data were especially sparse, and prediction intervals suggested estimated effects may not always be reliably replicated in different clinical scenarios.
  • Evident from the text: the additivity assumption for component network meta-analysis was violated for length of stay, requiring an interaction model; most included trials were at moderate or high risk of bias; no included studies reported patient or public partnership; and distinction between sex and gender in included studies was poor.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1136/bmj-2024-081164

Cites

65 of 65 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 33 cited sources checked · 0 supported · 0 flagged

  • Findingown data

    186 unique randomised controlled trials with 15,684 participants were included.

    “186 unique randomised controlled trials with 15 684 participants were included.”
    • Also stated in: § Results · plain
      “resulting in the inclusion of 186 unique randomised controlled trials (n=15 684)”
    Quote in the paperSubstantial claim
  • Findingown data

    All interventions except isolated cognitive prehabilitation directionally reduced length of stay compared with usual care.

    “A network meta-analysis at the treatment level found that all interventions, except for isolated cognitive prehabilitation, directionally reduced length of stay compared with usual care (fig 3, length of stay).”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: The transitivity assumption holds for the network meta-analysis.
  • Findingown data

    No significant differences were noted between any other active treatment comparisons for length of stay.

    “no significant differences were noted between any other active treatment comparisons (see league tables in appendix 16).”
    Quote in the paperNot a substantial claim
    • The authors state this as an assumption: The transitivity assumption holds for the network meta-analysis.
  • Findingown data

    Combined exercise, nutrition, plus psychosocial prehabilitation versus usual care reduced the odds of postoperative complications (odds ratio 0.64, 95% CI 0.45 to 0.92; P score 0.59; very low certainty).

    “combined exercise, nutrition, plus psychosocial prehabilitation (odds ratio 0.64 (0.45 to 0.92); P score 0.59; very low certainty)”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: The transitivity assumption holds for the network meta-analysis.
  • Findingown data

    Isolated exercise prehabilitation versus usual care reduced length of stay (mean difference -0.93 days, 95% CI -1.27 to -0.58; P score 0.63; very low certainty).

    “isolated exercise prehabilitation ( –0.93 days (–1.27 to –0.58); P score 0.63; very low certainty)”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: The transitivity assumption holds for the network meta-analysis.
  • May combine two claims. 37
  • Classified as probably not a substantial claim. 26

  • May combine two claims.

    Findingnone given

    Small study effects may have been present for exercise, nutrition, plus psychosocial and isolated nutritional prehabilitation for complications and length of stay outcomes; isolated exercise for health related quality of life; and exercise, nutrition, plus psychosocial prehabilitation for physical recovery.

    “Small study effects may have been present for exercise, nutrition, plus psychosocial and isolated nutritional prehabilitation for complications and length of stay outcomes; isolated exercise for health related quality of life; and exercise, nutrition, plus psychosocial prehabilitation for physical recovery.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    Among included trials, 43 (23%) were low risk of bias, 66 (36%) were moderate, and 77 (41%) were high risk.

    “Among included trials, 43 (23%) were low risk of bias, 66 (36%) were moderate, and 77 (41%) were high risk (fig 1, appendix 13).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    All outcomes except physical recovery had one closed loop; physical recovery had a star-shaped network.

    “All outcomes except physical recovery had one closed loop; physical recovery had a star-shaped network.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    An exercise prehabilitation component was reported in 133 randomised controlled trials (72%), nutritional in 68 (37%), psychosocial in 31 (17%), and cognitive in four (2%).

    “An exercise prehabilitation component was reported in 133 randomised controlled trials (72%), nutritional in 68 (37%), psychosocial in 31 (17%), and cognitive in four (2%) (appendix 11).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    Statistical heterogeneity was substantial for length of stay, health related quality of life, and physical recovery; none of the a priori specified effect modifiers meaningfully explained this variability.

    “Statistical heterogeneity was substantial for length of stay, health related quality of life, and physical recovery; however, none of our a priori specified effect modifiers meaningfully explained this variability.”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: The transitivity assumption holds for the network meta-analysis.

  • May combine two claims.

    Findingown data

    No evidence of global inconsistency was suggested for any endpoint, while a minor deviation in local tests of inconsistency for complications downgraded certainty ratings for one comparison.

    “No evidence of global inconsistency was suggested for any endpoint, while a minor deviation detected in the local tests of inconsistency for the complications outcome downgraded certainty ratings for one comparison.”
    Quote in the paperNot a substantial claim
    • The authors state this as an assumption: The transitivity assumption holds for the network meta-analysis.

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

    Findingown data

    Complications were reported in 106 trials comprising 8816 participants.

    “Complications were reported in 106 trials comprising 8816 participants (fig 2, complications).”
    Quote in the paperNot a substantial claim

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

    Findingown data

    Physical recovery was measured on various scales, most commonly the six min walk test (34 studies).

    “was measured on various scales, most commonly the six min walk test (34 studies).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    Meta-regression on surgery type did not significantly improve model fit for length of stay, while meta-regression on the mean length of stay of the control group did significantly improve model fit.

    “Meta-regression on surgery type did not significantly improve model fit, while meta-regression on the mean length of stay of the control group did significantly improve model fit (appendix 16).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    Isolated nutrition and multicomponent interventions that included nutrition significantly improved all critical outcomes and had a high probability of being the most efficacious component in all component network meta-analysis analyses.

    “isolated nutrition and multicomponent interventions that included nutrition significantly improved all critical outcomes and had a high probability of being the most efficacious component in all component network meta-analysis analyses.”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: The effects of prehabilitation components are additive (no interaction between components) in the component network meta-analysis model.

  • May combine two claims.

    Findingown data

    Based on P scores rankings in treatment level network meta-analysis, isolated exercise and multicomponent interventions that included exercise were typically most probable to improve critical outcomes, while isolated psychosocial and cognitive interventions and usual care were less probable to improve outcomes.

    “Based on P scores rankings, in treatment level network meta-analysis, isolated exercise and multicomponent interventions that included exercise were typically most probable to improve critical outcomes, while isolated psychosocial and cognitive interventions and usual care were less probable to improve outcomes (fig 4).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Our results show that the overall certainty in prehabilitation efficacy remains mostly low to very low, in keeping with previous reviews.

    “Our results show that the overall certainty in prehabilitation’ efficacy remain mostly low to very low, in keeping with previous reviews.1 14 56 57”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites 1 14 56 57

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  • May combine two claims.

    Findingown data

    Certainty in pooled estimates for all components and combinations was downgraded because of within trial bias and imprecision across all outcomes, and data for health related quality of life and physical recovery were especially sparse.

    “While certainty in pooled estimates for all components and combinations was downgraded because of within trial bias and imprecision across all outcomes, data for health related quality of life and physical recovery were especially sparse.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Certainty in effect estimates for direct comparisons for length of stay was moderate for exercise plus nutrition and exercise, nutrition, plus psychosocial versus usual care, and very low for all others.

    “Certainty in the effect estimates for direct comparisons was moderate for exercise plus nutrition and exercise, nutrition, plus psychosocial versus usual care, and very low for all others.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    Health related quality of life was reported in 53 randomised controlled trials (n=4135) and measured on various scales, most commonly the SF-36 or SF-12 physical component score (n=14 studies; 26%) and the EQ-5D visual analogue scale (n=8; 15%).

    “Health related quality of life was reported in 53 randomised controlled trials (n=4135; fig 2, panel C) and measured on various scales, most commonly the SF-36 or SF-12 physical component score (n=14 studies; 26%) and the EQ-5D visual analogue scale (n=8; 15%).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    Certainty of evidence from direct comparisons was very low for all treatment comparisons for complications except exercise plus nutrition versus usual care, which was low.

    “Certainty of evidence from direct comparisons were rated as very low for all treatment comparisons except exercise plus nutrition versus usual care (low;”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    Health related quality of life and physical recovery networks became sparse when studies that had a high risk of bias were removed, resulting in widening of confidence intervals for exercise, although the magnitude of effect changed minimally in both analyses.

    “Health related quality of life and physical recovery networks became sparse when studies that had a high risk of bias were removed, resulting in widening of confidence intervals for exercise, although the magnitude of effect changed minimally in both analyses.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    Certainty in direct effect estimates for health related quality of life was moderate for nutrition v usual care, low for exercise plus nutrition and exercise plus psychosocial v usual care and exercise v psychosocial, and very low for exercise, psychosocial, exercise plus cognitive, and exercise, nutrition, plus psychosocial v usual care.

    “Certainty in direct effect estimates were moderate for one intervention (nutrition v usual care), low for three (exercise plus nutrition and exercise plus psychosocial v usual care; exercise v psychosocial) and very low for four comparisons (exercise, psychosocial, exercise plus cognitive, and exercise, nutrition, plus psychosocial v usual care).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Sparse data related to psychological and cognitive prehabilitation, as well as limited representation of these components across surgery types, may have limited the ability to provide robust estimates of their efficacy.

    “Sparse data related to psychological and cognitive prehabilitation, as well as limited representation of these components across surgery types, may have limited our ability to provide robust estimates of their efficacy.”
    Quote in the paperSubstantial claim

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

    Premisecitation

    Many reviews, including an umbrella review of 55 unique systematic reviews, suggest that prehabilitation may have protective effects in reducing complications, length of stay, and improving functional recovery.

    “Many reviews,11 12 13 14 including an umbrella review that synthesised 55 unique systematic reviews,1 suggest that prehabilitation may have protective effects in reducing complications, length of stay, and improving functional recovery.”
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    Study design and conductcitation

    Effects from small studies (potential publication bias) were assessed through contour-enhanced funnel plots.

    “Effects from small studies (potential publication bias) were assessed through visual inspection of contour-enhanced funnel plots and incorporated into assessments of the certainty of the evidence.36 47”
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    • cites [47] NMAstudio. https://www.nmastudioapp.com/ (accessed 19 March 2024)

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

    Study design and conductown data

    Data extraction used a standardised collection form designed a priori, with each data point extracted by a first reviewer and verified by a lead extractor.

    “Once the final set of included randomised controlled trials was identified, data were extracted using a standardised collection form designed a priori for this study (appendix 4). Each data point was extracted by a first reviewer and verified by one of two lead data extractors.”
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    Study design and conductown data

    Screening of titles and abstracts, and full text review, were conducted in duplicate by two independent reviewers.

    “Screening of titles and abstracts, and then full text review, were conducted in duplicate by two independent reviewers using DistillerSR (Evidence Partners, Ottawa, Canada).”
    Quote in the paperNot a substantial claim

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    Study design and conductown data

    Between-trial heterogeneity and appropriateness of the transitivity assumption were assessed using box plots, bar charts, and evidence tables.

    “Between trial heterogeneity and appropriateness of the transitivity assumption for network meta-analysis were assessed using box plots, bar charts, and evidence tables to examine differences in potential study-level effect modifiers”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: The transitivity assumption holds for the network meta-analysis.

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    Study design and conductnone given

    Missing data were sought directly from study authors with at least two emails sent at least two weeks apart before data were considered missing.

    “Missing data were sought directly from study authors, with at least two emails sent at least two weeks apart before data were considered missing.”
    Quote in the paperNot a substantial claim

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    Interpretationcitation

    Because prehabilitation is often multicomponent and its components may modify each other's efficacy, pooling heterogeneous interventions limits understanding of which prehabilitation components or combinations are most likely to be efficacious.

    “As an often multicomponent intervention where different components (eg, exercise and nutrition) may modify the other’s efficacy,7 19 this limits our ability to understand what prehabilitation components, or combinations of components, are most likely to be efficacious.”
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    Study design and conductcitation

    The additivity assumption was tested by comparing Q-statistics of the additive component network meta-analysis model and the treatment-level network meta-analysis model.

    “We tested the additivity assumption by comparing the difference in Cochrane’s Q-statistics of the additive component network meta-analysis model and the treatment level (ie, full-interaction) network meta-analysis model at a cut-off determined by the difference in the models’ degrees of freedom.20 49”
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    • The authors state this as an assumption: In additive component network meta-analysis, the effects of individual components are additive.

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    Study design and conductcitation

    The report was prepared in keeping with PRISMA, PRISMA network meta-analysis, and GRIPP2 guidance.

    “This report was prepared in keeping with guidance from the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) statement, the PRISMA statement extension for network meta-analysis,23 24 and the guidance for reporting involvement of patients and the public-2 checklist (appendix 1).25”
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    Premisecitation

    Most available systematic reviews of prehabilitation are rated as low quality and have not included patient and public perspectives.

    “most available systematic reviews are rated as low quality1 16 and have not included patient and public perspectives.1”
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    Study design and conductcitation

    Risk of bias assessments were duplicated using the Cochrane risk of bias tool.

    “All risk of bias assessments were duplicated, one by the study lead and a second by another reviewer, using the Cochrane risk of bias tool.35”
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    Study design and conductcitation

    The focus of the review was directly informed by three patients and 10 knowledge user partners using an integrated knowledge translation approach.

    “The focus of this review was directly informed by three patients and 10 knowledge user partners using an integrated knowledge translation approach.21 26”
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    • cites [26] Graham ID Tetroe J Pearson A . Turning Knowledge Into Action: Practical Guidance on how to Do Integrated Knowledge Translation Research. 1st ed. Lippincott Williams & Wilkins, 2014.

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  • May combine two claims.

    Premisecitation

    Reviews typically estimate one effect for either a single prehabilitation component or pool heterogeneous interventions together.

    “Reviews typically estimate one effect for either a single prehabilitation component (eg, exercise only) or pool heterogeneous interventions together.1 14 17 18”
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    Premisecitation

    Network meta-analysis and component network meta-analysis allow estimation of separate effects for specific combinations of components, and individual components, respectively, through direct and indirect comparisons.

    “Network meta-analysis and component network meta-analysis allow estimation of separate effects for specific combinations of components, and individual components, respectively, through direct and indirect comparisons.20”
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    Study design and conductcitation

    The search strategy was developed by an information specialist and peer reviewed using best practices before being run.

    “A search strategy was developed by an information specialist, and peer reviewed using best practices27 prior to performance in the following databases: Ovid Medline, Embase, the CINAHL, PsycINFO, Web of Science, and the Cochrane CENTRAL Register of Controlled Trials.”
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    Study design and conductreasoning

    Four critical outcomes were prespecified based on input from patients, clinicians, health system leaders, and scientists.

    “Using an integrated knowledge translation approach, we were able to prespecify four outcomes based on input from patients, clinicians, health system leaders, and scientists:”
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    Study design and conductnone given

    Sensitivity analyses were considered for treatment-level network meta-analysis to explore heterogeneity or inconsistency.

    “We considered several sensitivity analyses for the treatment level network meta-analysis to explore evidence of heterogeneity or inconsistency, or both.”
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    Study design and conductcitation

    Consistency within treatment-level network meta-analysis was assessed using global and local tests.

    “Consistency within treatment level network meta-analysis was assessed using global (ie, design-by-treatment interaction test41) and local tests (ie, comparison of direct and indirect treatment effects, using a back-calculation approach42).”
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    • The authors state this as an assumption: The transitivity assumption holds for the network meta-analysis.

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    Study design and conductcitation

    The systematic review protocol was prospectively registered (CRD42023353710) and published.

    “A protocol was developed, prospectively registered (CRD42023353710), and published.22”
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    Study design and conductnone given

    Frequentist random-effects network meta-analysis models were prespecified for all outcomes.

    “We prespecified use of frequentist random-effects network meta-analysis models for all outcomes.”
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    • The authors state this as an assumption: The transitivity assumption holds for the network meta-analysis.

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    Study design and conductcitation

    Certainty of treatment effect estimates was assessed using the CINeMA approach covering six domains of bias.

    “Certainty of treatment effect estimates for each outcome at the treatment level were assessed using the Confidence in Network Meta-Analysis (CINeMA) approach, covering six domains of bias: within study bias, across study bias, indirectness, imprecision, heterogeneity, and inconsistency.50 51”
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    Study design and conductcitation

    The ROB-MEN tool was used to assess reporting bias, including effects from small studies.

    “We used the risk of bias due to missing evidence in network meta-analysis (ROB-MEN) tool to assess reporting bias, which includes the assessment of effects from small studies.52”
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    Study design and conductnone given

    This review was conducted according to best practices for systematic reviews, network meta-analyses, and component network meta-analyses.

    “This review was conducted according to best practices for systematic reviews, network meta-analyses, and component network meta-analyses.”
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    Interpretationown data

    Surgery type may not be an important modifier of prehabilitation efficacy and might support design and evaluation of prehabilitation programmes that could span multiple surgical populations.

    “This suggests that surgery type may not be an important modifier of prehabilitation efficacy and might support design and evaluation of prehabilitation programmes that could span multiple surgical populations.”
    Quote in the paperSubstantial claim

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    Interpretationown data

    While trial level risk of bias and imprecision reduced the certainty of effect estimates, pooled effect sizes may represent clinically meaningful improvements, and estimates for exercise and nutrition were robust after exclusion of high risk of bias trials.

    “While trial level risk of bias and imprecision reduced the certainty of our effect estimates, pooled effect sizes may represent clinically meaningful improvements, and estimates for exercise and nutrition were robust after exclusion of high risk of bias trials.”
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    Study design and conductnone given

    Partners were involved in all subsequent stages of the review, including interpretation of results and reporting.

    “Partners were also involved in all subsequent stages of the review, including interpretation of results and reporting.”
    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

    The protocol was developed in partnership with patients, clinicians, health system leaders, and researchers, and was registered and published a priori.

    “Our protocol was developed in partnership with patients, clinicians, health system leaders, and researchers, and was registered and published a priori.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationown data

    The interaction terms suggested that the incremental effects of the exercise and nutrition components were reduced in the other's presence, and inclusion of a psychosocial component further reduced the expected effect of the intervention.

    “However, the interaction terms suggested that the incremental effects of the exercise and nutrition components were reduced in the other’s presence (ie, the reduction in length of stay was not as large as their sum), and inclusion of a psychosocial component further reduced the expected effect of the intervention.”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: In additive component network meta-analysis, the effects of individual components are additive.

  • May combine two claims.

    Interpretationown data

    Prehabilitation likely has moderate effects on complications and length of stay.

    “While our results suggest that prehabilitation likely has moderate effects on complications and length of stay”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Premisecitation

    Previous reviews and partners have identified that prehabilitation's efficacy in improving outcomes may be heterogenous.

    “Previous reviews and our partners have identified that prehabilitation’s efficacy in improving outcomes may be heterogenous.1 14 18 54”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites 1 14 18 54

      Not checked in the free run.

  • May combine two claims.

    Interpretationown data

    Consistent and potentially meaningful effect estimates suggest that exercise prehabilitation, nutritional prehabilitation, and multicomponent interventions including exercise may benefit adults preparing for surgery and could be considered in clinical care.

    “Consistent and potentially meaningful effect estimates suggest that exercise prehabilitation, nutritional prehabilitation, and multicomponent interventions including exercise may benefit adults preparing for surgery and could be considered in clinical care.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    Leading contributors to the uncertainty about prehabilitation components are a lack of rigour in conduct of existing reviews, use of quantitative methods that do not align with the multicomponent nature of prehabilitation interventions, and risk of bias at the trial level.

    “While this uncertainty is multifactorial, leading contributors are a lack of rigour in conduct of existing reviews, use of quantitative methods that do not align with the multicomponent nature of prehabilitation interventions, and risk of bias at the trial level.1”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [1] source

      Not checked in the free run.

  • May combine two claims.

    Interpretationown data

    The strongest evidence supports isolated exercise and nutritional prehabilitation, as well as multicomponent interventions including exercise.

    “The strongest evidence supports isolated exercise and nutritional prehabilitation, as well as multicomponent interventions including exercise.”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: The effects of prehabilitation components are additive (no interaction between components) in the component network meta-analysis model.

  • May combine two claims.

    Interpretationown data

    In a systematic review with network and component network meta-analyses at the treatment level, evidence was found for prehabilitation efficacy with moderate effect sizes in reducing complications rates, and potentially clinically meaningful improvements in length of stay, health related quality of life, and physical recovery for adults preparing for major surgery.

    “In a systematic review with network and component network meta-analyses at the treatment level, we found evidence for prehabilitation efficacy with moderate effect sizes in reducing complications rates, and potentially clinically meaningful improvements in length of stay, health related quality of life, and physical recovery for adults preparing for major surgery.”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: The effects of prehabilitation components are additive (no interaction between components) in the component network meta-analysis model.

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

    Interpretationnone given

    Some heterogeneity could be due to different timing of outcome ascertainment within prespecified follow up periods.

    “Some heterogeneity could also be due to different timing of outcome ascertainment within prespecified follow up periods.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationown data

    Multicomponent interventions that include exercise, as well as isolated exercise and nutrition, are most likely to improve complication rates, length of stay, health related quality of life and physical recovery after surgery.

    “Multicomponent interventions that include exercise, as well as isolated exercise and nutrition are most likely to improve complication rates, length of stay, health related quality of life and physical recovery after surgery”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: The effects of prehabilitation components are additive (no interaction between components) in the component network meta-analysis model.

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

    Interpretationreasoning

    Heterogeneity within pooled components may account for some of the estimated imprecision.

    “Heterogeneity within pooled components (eg, different types of exercise programmes were all pooled as exercise interventions) may also account for some of the estimated imprecision.”
    Quote in the paperNot a substantial claim
56 of 56

  • The authors state this as an assumption.

    In additive component network meta-analysis, the effects of individual components are additive.

    “Additive component network meta-analysis assumes that the effects of individual components are additive (ie, the effect of a treatment comprised of exercise and nutrition components would be the sum of the expected effects of exercise and nutrition alone).20”

  • The authors state this as an assumption.

    The transitivity assumption holds for the network meta-analysis.

    “Between trial heterogeneity and appropriateness of the transitivity assumption for network meta-analysis were assessed using box plots, bar charts, and evidence tables to examine differences in potential study-level effect modifiers”

  • The authors state this as an assumption.

    The effects of prehabilitation components are additive (no interaction between components) in the component network meta-analysis model.

    “For the component network meta-analysis model, no evidence suggested violation of the additivity assumption from statistical tests.”
    “For the component network meta-analysis model, no evidence from statistical testing suggested that the additivity assumption was violated.”
3 of 3

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?

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.

  • Claim that isolated nutrition significantly improved every outcome conflicts with quality-of-life result

    Major

    The discussion says isolated nutrition significantly improved all critical outcomes, but its reported confidence interval for health related quality of life crosses zero.

  • Physical-recovery certainty is described as both low and very low

    Minor

    The physical-recovery section rates isolated exercise as low certainty, then says the effect estimates were very low certainty for all treatment comparisons.

  • Claim about nutrition-containing interventions conflicts with length-of-stay result

    Minor

    The discussion says multicomponent interventions containing nutrition significantly improved all critical outcomes, but the reported confidence interval for exercise plus nutrition on length of stay crosses zero.

3 of 3

Cites

Flagged first, then by citations

Research works printed but not linked: 2

  1. 10.1016/S0140-6736(18):31131-0 · DOI
  2. Graham ID Tetroe J Pearson A . Turning Knowledge Into Action: Practical Guidance on how to Do Integrated Knowledge Translation Research. 1st ed. Lippincott Williams & Wilkins, 2014.

Cited by

Sorted by citations

Related

Authors
McIsaac, D. I., Kidd, G., Gillis, C., Branje, K., Al-Bayati, M., Baxi, A., Grudzinski, A. L., Boland, L., Veroniki, A.-A., Wolfe, D., & Hutton, B.
Affiliations
  • University of Ottawa (CA)
  • Ottawa Hospital Research Institute (CA)
  • McGill University (CA)
  • Public Health Agency of Canada (CA)
  • St. Michael's Hospital (CA)
Corresponding author
McIsaac, Daniel I
ORCID
Venue
BMJ
Publisher
BMJ
Published
2025-01-22
Volume
388
Pages
e081164
ISSN
1756-1833 (ISSN-L)
DOI
10.1136/bmj-2024-081164
PMC
PMC11752451
OpenAlex
W4406714616
Semantic Scholar
ea2087b6c3692d8bf09336124337cbadda25d3a2
Cited by
168
References
65
Citations by year
2026: 121 · 2025: 47
FWCI
40.35
Type
journal article
Language
en
Open access
Licence
Locations
  • BMJ (publishedVersion, cc-by-nc)
  • PubMed (publishedVersion)
  • PubMed Central (publishedVersion, cc-by-nc)
Funders
  • University of Ottawa
  • Canadian Institutes of Health Research (202109PJK)
Topics
  • Health Sciences › Medicine › Surgery › Enhanced Recovery After Surgery
  • Health Sciences › Medicine › Cardiology and Cardiovascular Medicine › Cardiac, Anesthesia and Surgical Outcomes
  • Health Sciences › Medicine › Critical Care and Intensive Care Medicine › Intensive Care Unit Cognitive Disorders
Keywords
prehabilitation, physical activity, nutrition, cognitive intervention, psychosocial interventions, postoperative complications, length of hospital stay, health-related quality of life, physical recovery, major surgery
MeSH terms
Preoperative Exercise, Humans, Length of Stay, Postoperative Complications, Preoperative Care, Quality of Life, Randomized Controlled Trials as Topic, Treatment Outcome

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 2026-10-09.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-09.

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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