Empirical comparison of subgroup effects in conventional and individual patient data meta-analyses
- 4 July 2008
- journal article
- research article
- Published by Cambridge University Press (CUP) in International Journal of Technology Assessment in Health Care
- Vol. 24 (3), 358-361
- https://doi.org/10.1017/s0266462308080471
Abstract
Objectives:Individual patient data (IPD) meta-analyses have been proposed as a major improvement in meta-analytic methods to study subgroup effects. Subgroup effects of conventional and IPD meta-analyses using identical data have not been compared. Our objective is to compare such subgroup effects using the data of six trials (n= 1,643) on the effectiveness of antibiotics in children with acute otitis media (AOM).Methods:Effects (relative risks, risk differences [RD], and their confidence intervals [CI]) of antibiotics in subgroups of children with AOM resulting from (i) conventional meta-analysis using summary statistics derived from published data (CMA), (ii) two-stage approach to IPD meta-analysis using summary statistics derived from IPD (IPDMA-2), and (iii) one-stage approach to IPD meta-analysis where IPD is pooled into a single data set (IPDMA-1) were compared.Results:In the conventional meta-analysis, only two of the six studies were included, because only these reported on relevant subgroup effects. The conventional meta-analysis showed larger (age < 2 years) or smaller (age ≥ 2 years) subgroup effects and wider CIs than both IPD meta-analyses (age < 2 years: RDCMA-21 percent, RDIPDMA-1-16 percent, RDIPDMA-2-15 percent; age ≥2 years: RDCMA-5 percent, RDIPDMA-1-11 percent, RDIPDMA-2-11 percent). The most important reason for these discrepant results is that the two studies included in the conventional meta-analysis reported outcomes that were different both from each other and from the IPD meta-analyses.Conclusions:This empirical example shows that conventional meta-analyses do not allow proper subgroup analyses, whereas IPD meta-analyses produce more accurate subgroup effects. We also found no differences between the one- and two-stage meta-analytic approaches.Keywords
This publication has 15 references indexed in Scilit:
- An overview of methods and empirical comparison of aggregate data and individual patient data results for investigating heterogeneity in meta‐analysis of time‐to‐event outcomesJournal of Evaluation in Clinical Practice, 2005
- Meta-analysis of individual patient data from randomized trials: a review of methods used in practiceClinical Trials, 2005
- Nonsevere Acute Otitis Media: A Clinical Trial Comparing Outcomes of Watchful Waiting Versus Immediate Antibiotic TreatmentPediatrics, 2005
- A randomized, double-blind, placebo-controlled noninferiority trial of amoxicillin for clinically diagnosed acute otitis media in children 6 months to 5 years of ageCMAJ : Canadian Medical Association Journal, 2005
- To IPD or not to IPD?Evaluation & the Health Professions, 2002
- A Comparison of Meta-analytic Results Using Literature vs Individual Patient DataJAMA, 1995
- A comparison of meta-analytic results using literature vs individual patient data. Paternal cell immunization for recurrent miscarriagePublished by American Medical Association (AMA) ,1995
- Meta-analysis of the literature or of individual patient data: is there a difference?The Lancet, 1993
- Co-amoxiclav in recurrent acute otitis media: placebo controlled study.BMJ, 1991
- Acute red ear in children: controlled trial of non-antibiotic treatment in general practice.BMJ, 1991