Using the 1983 norms for the MMPI: code type frequencies in four clinical samples

MMPI responses obtained from a large random sample of midwestern adults who were 18 through 99 years old and had no physically or mentally handicapping condition yielded a pattern significantly different from the pattern of the original norms. From these data, two new kinds of normative tables have been developed: Norms that reflect, for each sex, the response pattern of the general adult population, and a set of tables, separate for each sex, that allow comparisons to be based on age. In addition, the traditional scoring procedures based on a linear transformation that maintains any underlying skewness of the raw score distribution has been replaced by procedures that yield normalized T scores. The changes that are apparent at the item and scale level are also evident in the frequency with which certain 1- and 2-point codes occur in normal and clinical samples. These changes are apt to make our interpretive statements more meaningful because they are based on contemporary norms.