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Empirical comparison of subgroup effects in conventional and individual patient data meta-analyses

Published online by Cambridge University Press:  04 July 2008

Laura Koopman ,
Geert J. M. G. van der Heijden ,
Arno W. Hoes ,
Diederick E. Grobbee  and
Maroeska M. Rovers
Laura Koopman
Affiliation:
University Medical Center Utrecht
Geert J. M. G. van der Heijden
Affiliation:
University Medical Center Utrecht
Arno W. Hoes
Affiliation:
University Medical Center Utrecht
Diederick E. Grobbee
Affiliation:
University Medical Center Utrecht
Maroeska M. Rovers
Affiliation:
University Medical Center Utrecht
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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

Conventional meta-analysesIndividual patient data meta-analysesSubgroup analysesMeta-analyses methods
Type
RESEARCH REPORTS
Information
International Journal of Technology Assessment in Health Care , Volume 24 , Issue 3 , July 2008 , pp. 358 - 361
Copyright
Copyright © Cambridge University Press 2008

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References

REFERENCES

1. Appelman, CL, Claessen, JQ, Touw-Otten, FW, et al. Co-amoxiclav in recurrent acute otitis media: Placebo controlled study. BMJ. 1991;303:1450-1452.CrossRefGoogle ScholarPubMed
2. Burke, P, Bain, J, Robinson, D, et al. Acute red ear in children: Controlled trial of non-antibiotic treatment in general practice. BMJ. 1991;303:558-562.CrossRefGoogle ScholarPubMed
3. Clarke, MJ, Stewart, LA. Obtaining individual patient data from randomised controlled trials. In: Egger, M, Smith, GD, Altman, DG, eds. Systematic reviews in health care: Meta-analysis in context. London: BMJ Publishing Group; 2001:109-121.Google Scholar
4. Damoiseaux, RA, Van Balen, FA, Hoes, AW, et al. Primary care based randomized, double blind trial of amoxicillin versus placebo for acute otitis media in children aged under 2 years. BMJ. 2000;320:350-354.CrossRefGoogle ScholarPubMed
5. Jeng, GT, Scott, JR, Burmeister, LF. A comparison of meta-analytic results using literature vs individual patient data; paternal cell immunization for recurrent miscarriage. JAMA. 1995;274:830-836.CrossRefGoogle ScholarPubMed
6. Le Saux, N, Gaboury, I, Baird, M, et al. A randomized, double-blind, placebo-controlled noninferiority trial of amoxicillin for clinically diagnosed acute otitis media in children 6 months to 5 years of age. CMAJ. 2005;172:335-341.CrossRefGoogle ScholarPubMed
7. Little, P, Gould, C, Williamson, I, et al. Pragmatic randomised controlled trial of two prescribing strategies for childhood acute otitis media. BMJ. 2001;322:336-342.CrossRefGoogle ScholarPubMed
8. McCormick, DP, Chonmaitree, T, Pittman, C, et al. Nonsevere acute otitis media: A clinical trial comparing outcomes of watchful waiting versus immediate antibiotic treatment. Pediatrics. 2005;115:1455-1465.CrossRefGoogle ScholarPubMed
9. Olkin, I, Sampson, A. Comparison of meta-analysis versus analysis of variance of individual patient data. Biometrics. 1998;54:317-322.CrossRefGoogle ScholarPubMed
10. Rovers, MM, Glasziou, P, Appelman, CL, et al. Antibiotics for acute otitis media: A meta-analysis with individual patient data. Lancet. 2006;368:1429-1435.CrossRefGoogle ScholarPubMed
11. Simmonds, MC, Higgins, JP, Stewart, LA, et al. Meta-analysis of individual patient data from randomized trials: A review of methods used in practice. Clin Trials. 2005;2:209-217.CrossRefGoogle ScholarPubMed
12. Smith, CT, Williamson, PR, Marson, AG. 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 outcomes. J Eval Clin Pract. 2005;11:468-478.CrossRefGoogle ScholarPubMed
13. Steinberg, KK, Smith, SJ, Stroup, DF, et al. Comparison of effect estimates from a meta-analysis of summary data from published studies and from a meta-analysis using individual patient data for ovarian cancer studies. Am J Epidemiol. 1997;145:917-925.CrossRefGoogle ScholarPubMed
14. Stewart, LA, Parmar, MK. Meta-analysis of the literature or of individual data: Is there a difference? Lancet. 1993;341:418-422.CrossRefGoogle ScholarPubMed
15. Stewart, LA, Tierney, JF. To IPD or not to IPD? Advantages and disadvantages of systematic reviews using individual patient data. Eval Health Prof. 2002;25:76-97.CrossRefGoogle ScholarPubMed