An assessment of the use of the continuity correction for sparse data in meta-analysis

A problem which occurs in the practice of meta-analysis is that one or more component studies may have sparse data, such as zero events in the treatment and control groups. Two possible approaches were explored using simulations. The corrected method, in which one half was added to each cell was compared to the uncorrected method. These methods were compared over a range of sparse data situations in terms of coverage rates using three summary statistics: the Mantel-Haenszel odds ratio and the Dersimonian and Laird odds ratio and rate difference. The uncorrected method performed better only when using the Mantel-Haenszel odds ratio with very little heterogeneity present. For all other sparse data applications, the continuity correction performed better and is recommended for use in meta-analyses of similar scope.