Writing a good cookbook: II. A synthesis of MMPI high-point code system study effect sizes

This article continues a review of the high-point code system studies of th e MMPI. Using meta-analytic methods, we conducted an analysis of effect siz es associated with these studies. Effect sizes were on average small. The f inding is inconsistent both with the image of the MMPI as a powerful clinic al instrument and with at least some of the previous evidence on MMPI effec t sizes. The finding is discussed in some de tail, including potential sour ces of bias in the analysis, comparisons with previous statistical reviews, and reasons clinicians place a high degree of faith in interpretations bas ed on the high-point code. We believe the existing high-point code system r esearch may not adequately reflect the true validity of these codes.