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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: INTRODUCTION, METHODS, RESULTS. Meshes: Depressive Disorder, Major, Diagnostic and Statistical Manual of Mental Disorders, Female, Humans, Male, Reproducibility of Results, Time Factors, Young Adult.
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Is two weeks the optimum duration criterion for major depression? Context: A clinically useful diagnostic classification should identify most patients who are treated. To our surprise, DSM-IV criteria for major depressive episodes (MDE) detected fewer than 50% of a community sample (the Zurich study) who had received treatment for depression.1 Treated subjects often experience episodes lasting under 2 weeks, or with fewer symptoms than required for a DSM diagnosis. Our paper focuses on the validity and clinical relevance of the length of depressive syndromes, defined by the presence of 5 or more of 9 diagnostic symptoms (DSM-IV). We found depressive syndromes lasting under 2 weeks to be highly prevalent, and those lasting 4+ days to have equal validity (family history, age of onset, course) and treatment rates to episodes of 2-4 weeks.
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The 2-week criterion for MDE would appear questionable. Our results need confirmation by larger epidemiological studies.