Obstetrician-gynecologists' decision making about the diagnosis of major depressive disorder and premenstrual dysphoric disorder

Major depressive disorder (MDD) is underdiagnosed and undertreated in ambulatory care settings [1-4] including gynecologic practices [5]. Far less is known about the diagnosis of Premenstrual Dysphoric Disorder (PMDD). Three hundred and thirty-five gynecologists responded to mailed questionnaires that used descriptive scenarios as analogues to clinical cases. Questionnaire recipients were randomly selected to receive either a MDD or PMDD version of the questionnaire. Respondents were less accurate when diagnosing MDD cases (48%, accuracy; p = 0.526), than PMDD cases (80% accuracy; p < 0.001), but were significantly more confident about their probability ratings of MDD cases, t = 2.57, p < 0.02. Qualitative analysis suggested that less accurate MDD respondents did not prioritize case data according to DSM-IV criteria, whereas almost all PMDD respondents made use of valid reasoning strategies. Respondents did not take base rates into account when deciding about the probability of either affective disorder. Results imply that gynecologists employ cognitive strategies that result in accurate diagnostic judgments about PMDD, but overconfidence, lack of attention to DSM-IV criteria and base rate neglect could hinder clinical decisions about MDD, and may contribute to underdiagnosis of depression.