When poorly conducted systematic reviews and meta-analyses can mislead: a critical appraisal and update of systematic reviews and meta-analyses examining the effects of probiotics in the treatment of functional constipation in children
Open accessAbstract
Background Recent systematic reviews and meta-analyses on the efficacy of probiotics in the treatment of functional constipation in children have yielded conflicting results. Objectives The aim of this study was to critically review and update the evidence in this field by mapping all the steps involved against those reported in previous reviews, in an attempt to understand the nature of their conflicting results. Methods Four literature databases, trial registries, and citations were searched through December 1, 2018. We included randomized controlled trials (RCTs) that assessed the effects of probiotics compared with placebo or treatment as usual on defecation frequency [bowel movements (BMs)/wk] or treatment success rates in children with functional constipation. Independent reviewers extracted the data and assessed risk of bias in each RCT. Data were pooled with (inverse variance) random-effects models. Results We identified 17 RCTs, of which 14 and 11 provided sufficient data to enable meta-analysis of the effects of probiotics compared with control on defecation frequency (n = 965) or treatment success (n = 835), respectively. When compared to (any) control intervention, probiotics did not significantly increase defecation frequency [weighted mean difference (WMD): 0.28 BMs/wk; 95% CI: -0.12, 0.69; P = 0.165] but were more efficacious in achieving treatment success (RR: 1.24; 95% CI: 1.03, 1.50; P = 0.024). These effects did not differ by type of control (i.e., active o…
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Publication bias may have limited the research studies included in this review.
“In addition, we found that publication bias may have limited the research studies included in this review; a recent systematic review of probiotics in the management of constipation also reported evidence of publication bias (Harris 2019).”
From Probiotics for treating acute infectious diarrhoea (2020) · cites this paper as Harris 2019
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- Authors
- Harris, R. G., Neale, E. P., & Ferreira, I.
- Affiliations
- University of Wollongong (AU)
- Corresponding author
- Ferreira, Isabel
- Venue
- The American Journal of Clinical Nutrition
- Publisher
- Elsevier BV
- Published
- 2019-07
- Volume
- 110
- Issue
- 1
- Pages
- 177-195
- ISSN
- 0002-9165 (ISSN-L)
- OpenAlex
- W2945303180
- Cited by
- 38
- References
- 18
- Citations by year
- 2026: 3 · 2025: 2 · 2024: 6 · 2023: 6 · 2022: 2 · 2021: 8 · 2020: 10 · 2019: 1
- FWCI
- 0.95
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Licence
- Locations
- American Journal of Clinical Nutrition (publishedVersion)
- PubMed (publishedVersion)
- Research Online (University of Wollongong) (submittedVersion)
- Topics
- Health Sciences › Medicine › Gastroenterology › Gastrointestinal motility and disorders
- Social Sciences › Decision Sciences › Statistics, Probability and Uncertainty › Meta-analysis and systematic reviews
- Life Sciences › Agricultural and Biological Sciences › Food Science › Probiotics and Fermented Foods
- Keywords
- probiotics, functional constipation, pediatric constipation, stool frequency, treatment success, risk of bias, systematic review quality, meta-analysis heterogeneity, randomized controlled trials, coadjuvant therapy, risk of bias assessment, treatment success rate, risk of bias in meta-analysis, risk of bias in individual studies
- MeSH terms
- Systematic Reviews as Topic, Child, Constipation, Defecation, Humans, Meta-Analysis as Topic, Reproducibility of Results, Bias, Randomized Controlled Trials as Topic, Treatment Outcome, Probiotics
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