Clinic patients with diagnoses of either major depression or somatization disorder were given the MMPI. Women with somatization disorder had high scores on Keane's MMPI scale (PK) for posttraumatic stress disorder. Following the procedure for the MMPI-2 (46 of the 49 PK items and MMPI-2 norms), 59% of the women with somatization disorder and 21% of the women with major depression would have T scores > or = 65 on the MMPI-2 scale although none of them were known to have developed psychiatric disorder after exposure to a life threatening event. The PK scale has little use in the differential diagnosis of women patients with somatization disorder.