The large-sample relative efficiency of the Mantel-Haenszel estimator in the fixed-strata case.

The large-sample relative efficiency of the Mantel-Haenszel estimator psi MH of an odds ratio is investigated for the case in which the number of strata is fixed and the sample sizes within each stratum increase indefinitely. The results show that psi MH is very efficient over a wide range of designs likely to occur in practice. However, conditions are identified under which the relative efficiency of this widely used estimator can be unusually low.