Exploring Heterogeneity in Randomized Trials Via Meta-Analysis
- 1 January 1999
- journal article
- review article
- Published by Springer Science and Business Media LLC in Drug Information Journal
- Vol. 33 (1), 211-224
- https://doi.org/10.1177/009286159903300124
Abstract
Meta-analysis of clinical trials with heterogeneous results provides an opportunity to learn a great deal about variations in treatment effectiveness. Rather than computing a single summary estimate of a series of trials, it may be more informative to explore the effect that different study characteristics may make on treatment efficacy. Regression analysis offers a tool for these analyses. This paper outlines and applies hierarchical Bayesian models for this purpose, presenting two examples of meta-regression using summary data, in one of which results are compared with those from analysis of complete individual patient data. When covariates are not readily available, the event rate in the control group can become a surrogate covariate. An empirical study of 115 meta-analyses shows that this control rate is significantly correlated with the odds ratio about 15% of the time. This suggests that investigators should search for the causes of heterogeneity related to patient characteristics and treatment protocols to determine when treatment is most beneficial and that they should plan to study this heterogeneity in clinical trials.Keywords
This publication has 41 references indexed in Scilit:
- Exploratory or analytic meta-analysis: Should we distinguish between them?Journal of Clinical Epidemiology, 1995
- Importance of trends in the interpretation of an overall odds ratio in the meta‐analysis of clinical trialsStatistics in Medicine, 1994
- Indications for fibrinolytic therapy in suspected acute myocardial infarction: collaborative overview of early mortality and major morbidity results from all randomised trials of more than 1000 patientsThe Lancet, 1994
- Cholesterol lowering and mortality: the importance of considering initial level of risk.BMJ, 1993
- Long-term comparison between captopril and nifedipine in the progression of renal insufficiencyKidney International, 1992
- Intravenous magnesium sulphate in suspected acute myocardial infarction: results of the second Leicester Intravenous Magnesium Intervention Trial (LIMIT-2)The Lancet, 1992
- Long-Term Effects of Enalapril and Nicardipine on Urinary Albumin Excretion in Patients with Chronic Renal Insufficiency: A 1-Year Follow-UpAmerican Journal of Nephrology, 1991
- Cardiac rupture, mortality and the timing of thrombolytic therapy: A meta-analysisJournal of the American College of Cardiology, 1990
- Measurement of renal function in chronic renal diseaseKidney International, 1990
- Meta-analysis in clinical trialsControlled Clinical Trials, 1986