MMPI validity measures: a comparative study of original with alternative indices

A comparison was made of the original MMPI validity scales (L,F,K,F - K) with validity scales devised subsequently (TR, Ca, Ds, Mp, Ws - Wo) to determine which scales, the older or newer, were better, either alone or combined, in detecting fake-good, fake-bad, and careless responding. This was accomplished by having groups of subjects answer the MMPI first under standard conditions and then, 1 week later, under one of the falsifying conditions. A group of 40 psychiatric patients responded under standard and then fake-good conditions; a group of 40 university students responded under standard and then fake-bad conditions; and a group of 20 students responded under standard and then fake-careless conditions. Results indicate that both the traditional and newer validity indices were equally good at detecting fake-good responding. None of the indices was adequate in detecting careless responses. We conclude, as a consequence of this study, that the newer scales perform a clinically useful function when faking good is suspected on the MMPI.