Can adjustment disorder and depressive episode be distinguished? Results from ODIN.

BACKGROUND No large-scale epidemiological study has included adjustment disorders (AD) for consideration yet it is considered to be a common psychiatric diagnosis. METHODS Using a two stage screening method, those above a threshold score for possible caseness on the Beck Depression Inventory (BDI), were interviewed using SCAN to identify those with depressive episode and AD. Variables that might distinguish AD from depressive episode were examined. RESULTS The prevalence of AD was extremely low with one centre having no cases. Finland, the country with the highest prevalence, only achieved a frequency of 0.8% and 1%, respectively, for urban and rural sites. Logistic regression failed to identify any variables that independently differentiated AD from depressive episode. Findings relating to severity of symptoms using BDI were robust. LIMITATIONS The small sample size might have contributed to a failure to identify distinguishing features between AD and other disorders. CONCLUSIONS Reasons for the failure of even robust results, such as BDI severity, to distinguish AD from depressive episode are considered of which problems in conceptualising AD are the most likely. Further studies are required.