Reliability of lifetime diagnoses and symptoms in patients with a current psychiatric disorder.

In this study we assess the reliability of rating past psychiatric symptoms and lifetime diagnoses in a currently ill population using the SADS and RDC. Five raters from different centers interviewed 25 subjects in a short-interval test-retest design. Subjects had a wide diversity of affective and non-affective diagnoses and high levels of manifest psychopathology. Our results demonstrate that it is possible for raters from different research centers to reliably rate lifetime diagnoses and previous symptoms. Two important exceptions to the high reliability are the lifetime diagnoses of hypomania and the recurrent unipolar subtype of major depressive disorder, and we alert clinicians and researchers to be cautious when diagnosing these conditions. We conclude that the next step in measuring reliability should be a long-interval test-retest design with separate interviews conducted at the later assessment, one by the original rater and the other by a blind rater.