Validation of a modified version of the Menstrual Distress Questionnaire: a case for false attribution?

Attempts to define premenstrual syndrome (PMS) have relied heavily on the use of questionnaires such as the Menstrual Distress Questionnaire (MDQ). Unfortunately, little research to date has been directed towards the validation of such symptom checklists against more established diagnostic tests. The purpose of this study was to examine the predictive validity of a modified version of the MDQ using the Profile of Mood States (POMS), as well as to examine both tests’ ability to discriminate complainers of PMS (n = 54) from non-complainers (n = 27). Using MDQ symptom checklists, women monitored their moods on a daily basis while the POMS was administered weekly. The predictive validity of previously established symptom clusters of Negative Affect, Tension and Cognition were examined using 2 techniques. The first was to correlate the MDQ with the POMS. Both canonical and bivariate correlations were employed. The second technique was to compare the 2 tests’ ability to discriminate between women complaining and not complaining of PMS. Results showed a good overall correlation between the 2 tests; approximately 50% of the POMS variance was explained by the MDQ clusters. In addition, good correlations were found between the MDQ and the comparable subscales of the POMS: T, D and C. However, high intercorrelations were also found between these subscales and the MDQ subscales of Negative Affect and Tension. Multivariate analyses of variance showed that the MDQ differentiated between the 2 groups but the POMS did not. Further examination of the data suggested that the POMS, when administered weekly, was not as powerful a test in discriminating complainers from non-complainers. The results are discussed in the light of subject expectations.