Mood (affective) disorders (F3). Results from the ICD-10 field trial of the Diagnostic Criteria for Research in German-speaking countries.

The present study reports results of the ICD-10 research criteria trial concerning the diagnosis of affective disorders (section F3). On the basis of written case reports and videotapes a total of 451 clinicians from 34 centres in German-speaking countries prepared 2.228 diagnostic ratings on 39 different psychiatric patients. Three of the 39 cases met the diagnostic criteria for affective disorders, and 248 of the diagnostic assessments referred to these cases. The majority of clinicians rated the reliability, the ease and the suitability of the diagnostic criteria positively. The reliability of the affective disorders was extremely good, with a kappa of 0.93 in the range of 2-character diagnoses. The reliability of the 3-character categories was much smaller: Kappa values for depressive episode (F31) and recurrent depressive disorder (F33) were 0.68 and 0.54, respectively. The lowest concordance had a kappa value of 0.22 and was found in the case report of dysthymia (F34.1). Therefore a more precise definition of the diagnostic criteria for dysthymia would be desirable.