Contribution of generalized negative affect to elevated menstrual cycle symptom reporting.

We investigated women's belief that they suffered from premenstrual syndrome (PMS) by monitoring patterns of symptom reporting over a 5-week period in relation to the underlying trait of negative affect. We expected that women reporting high negative affect would be more likely to report menstrual cycle distress than those reporting low negative affect. One hundred twenty-one women rated the typical occurrence and severity of premenstrual changes on a retrospective questionnaire and then made daily ratings of their changes for the duration of one cycle. In addition, they completed a questionnaire measuring positive and negative affect. Data analysis revealed a clear subgroup whose retrospective reports of premenstrual change were not substantiated by the cycle of their daily ratings. Although this subgroup also reported more negative affect, the magnitude of the effect was relatively small. The possible contribution of both negative outlook and the meaning of the self-identified label of PMS are discussed.