Abstract: | In a longitudinal prospective study, mood fluctuations were assessed for evidence of premenstrual syndrome (PMS) as well as other menstrual, day of week, and lunar cyclicity. Volunteer participants from the community (60 women and 10 men) provided daily data for 12 to 18 weeks. Significant mood fluctuation was determined by a new nonparametric method using each individual's own standard deviation as a measure of marked change. Cyclicity was the norm; two thirds of both the women and men had one or more menstrual or lunar phases or days of the week that were markedly positive and/or negative, relative to their own range, but few experienced stereotypical cyclicity (PMS, Monday blues, full moon). About half the women whose prospective data met conservative criteria for PMS, met liberal criteria, or met neither criteria said they had PMS, and half in each group said they did not. |