Estimation of Some Epidemiological Measures of Association in Multiple Comparative Trials

Multiple comparative trials with binary outcomes are commonly used in biomedical research and other disciplines for estimating epidemiological measures by combining information from multiple comparative trials. The epidemiological measures are commonly estimated as a weighted average of summary statistics based on the 2 × 2 table data from each trial. Three of the most important epidemiological measures are frequently used: the risk ratio (RR), odds ratio (OR), and risk difference (RD). The RD/RR are preferable due to a more meaningful and interpretable treatment measure for binary outcome. The estimation procedures for estimating the overall RD/RR in multiple comparative trials with binary outcomes are very challenging and difficult, especially when the number of patients in a single trial is small and when the number of events is zero for some trials. Considering the above situations, we develop some efficient estimation procedures for estimating the overall RD/RR in multiple comparative trials with binary outcomes. We illustrate those estimation procedures by analyzing two real-life data sets obtained from multiple comparative trials in biomedical research.