+ Site Statistics
References:
54,258,434
Abstracts:
29,560,870
PMIDs:
28,072,757
+ Search Articles
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ PDF Full Text
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Translate
+ Recently Requested

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



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



American Journal of Clinical Nutrition 2019



Recent systematic reviews and meta-analyses on the efficacy of probiotics in the treatment of functional constipation in children have yielded conflicting results. 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. 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. 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 or inactive) intervention. However, in analyses confined to the RCTs that were free of high risk of bias (only 5), probiotics did not confer any beneficial effects on defecation frequency (WMD: -0.55 BMs/wk; 95% CI: -1.37, 0.26; P = 0.185) and achievement of treatment success (RR: 1.01; 95% CI: 0.90, 1.13; P = 0.873), compared with control interventions. The current evidence thus does not support the use of probiotics as a single or coadjuvant therapy for treatment of functional constipation in children and refutes recently published reviews reporting favorable effects of probiotics. Conflicting findings of previous reviews resulted from methodologic errors, highlighting the susceptibility of evidence synthesis to oversights in study selection, quality assessments, and data extraction and collation. This review was registered at PROSPERO as CRD42019119109.

(PDF emailed within 0-6 h: $19.90)

Accession: 066818895

Download citation: RISBibTeXText

PMID: 31127810

DOI: 10.1093/ajcn/nqz071


Related references

A critical appraisal of the methodology and quality of evidence of systematic reviews and meta-analyses of traditional Chinese medical nursing interventions: a systematic review of reviews. Bmj Open 6(11): E011514, 2018

Not All Systematic Reviews are Systematic: A Meta-review of the Quality of Current Systematic Reviews and Meta-analyses for Remote Monitoring in Heart Failure. Heart Lung & Circulation 22: S84-S85, 2013

Quality of reporting of systematic reviews and meta-analyses: PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses). Rofo 183(12): 1106-1110, 2012

Antiretroviral therapy for initial human immunodeficiency virus/AIDS treatment: critical appraisal of the evidence from over 100 randomized trials and 400 systematic reviews and meta-analyses. Clinical Microbiology and Infection 20(2): 114-122, 2014

The quality of reports of critical care meta-analyses in the Cochrane Database of Systematic Reviews: an independent appraisal. Critical Care Medicine 35(2): 589-594, 2007

Recent meta-analyses neglect previous systematic reviews and meta-analyses about the same topic: a systematic examination. Bmc Medicine 13: 82, 2015

Systematic reviews and meta-analyses on treatment of asthma: critical evaluation. Bmj 320(7234): 537-540, 2000

Evaluation of methodological quality of systematic reviews and meta-analyses: AMSTAR (A Measurement Tool for the Assessment of Multiple Systematic Reviews). Rofo 184(10): 937-940, 2013

Evaluating the methodologic quality of systematic reviews and meta-analyses. AMSTAR (A Measurement Tool for the Assessment of Multiple Systematic Reviews. Rofo 185(10): 937-940, 2014

Evidence-based medicine, systematic reviews, and guidelines in interventional pain management: part 3: systematic reviews and meta-analyses of randomized trials. Pain Physician 12(1): 35-72, 2009

Evidence-based medicine, systematic reviews, and guidelines in interventional pain management: part 6. Systematic reviews and meta-analyses of observational studies. Pain Physician 12(5): 819-850, 2009

Effects of fixed orthodontic brackets on oral malodor: A systematic review and meta-analysis according to the preferred reporting items for systematic reviews and meta-analyses guidelines. Medicine 97(14): E0233, 2018

Evidence-based medicine, systematic reviews, and guidelines in interventional pain management: Part 7: systematic reviews and meta-analyses of diagnostic accuracy studies. Pain Physician 12(6): 929-963, 2010

Cochrane reviews compared with industry supported meta-analyses and other meta-analyses of the same drugs: systematic review. Yearbook of Dermatology and Dermatologic Surgery 2007: 267-268, 2007

Cochrane reviews compared with industry supported meta-analyses and other meta-analyses of the same drugs: systematic review. Bmj 333(7572): 782, 2006