Previous studies devised various definitions and measurements for subtle-obvious ratings of MMPI items, but failed to distinguish two forms of subtlety: direction and irrelevanc. The former concerns score-key direction, and the latter items irrelevant to judge abnormality. In the present study, three rating methods were used. In the first, four experts rated item abnormality with a 4-point scale to indicate score-key direction, and also tried to detect irrelevant items. Second, 17 semi-experts made judgments of score-key directions. And the thied was the same as the first, except that the raters were non-experts. An analysis of the present results in comparison with findings of previous studies indicated that abnormality ratings of the present study and the index by Christian et al. (1978) were indices of direction subtlety, and irrelevant items of the present study and Wiener's (1948) subtle items were the indices of irrelevancy subtlety. Apparently, failure to distinguish the two forms has been responsible for inconsistent findings in the previous investigation of subtlety.

Key words: Minnesota Multiphasic Personality Inventory (MMPI) -the new Japanese version, item subtlety, score-key direction, irrelevant items