THE USE OF FISHERS-Z IN SCHMIDT-HUNTER-TYPE METAANALYSES

Over the past few years, there has been some dispute as to whether Fisher's Z or the Pearson correlation (r) should be used in Schmidt-Hunter-type meta-analyses. The two major reasons that Z has not been recommended are the possibly larger positive bins in estimating mean population correlation (M(rho)) and the problem of estimating the standard deviation of population correlations (SDrho). In this study, two new methods of estimating M(rho) and SDrho by using Z are suggested and tested by Monte Carlo simulations. The results show no consistent advantage to using r instead of Z or vice versa in estimating both M(rho) and SDrho In fact the estimated M(rho) and SDrho from all three methods were highly similar and were almost identical when rounded off.