RÉSUMÉ
<p><b>OBJECTIVE</b>To describe the current prevalence and distribution of all types of mental disorders in Zhejiang Province and use this data to develop a provincial mental health plan.</p><p><b>METHODS</b>Stratified multi-stage cluster randomization was used to identify 14 counties (cities), 70 townships (urban districts), 140 villages (urban neighborhoods) and 15,000 subjects > or = 15 years of age. Psychiatric nurses used an expanded version of the General Health Questionnaire (GHQ) to identify subgroups of subjects at high, moderate and low risk of having a mental disorder, then psychiatrists determined their diagnoses by administering a structured psychiatric examination (SCID) that employs American diagnostic criteria for mental disorders (DSM-IV) to 100% of high-risk, 40% of moderate-risk and 10% of low-risk subjects.</p><p><b>RESULTS</b>14 639 subjects completed the screening and 4,788 completed the psychiatric examination. The adjusted overall current rate of mental disorders was 17.3% (95% CI = 16.0%-18.7%), which dropped to 13.4% (12.2%-14.7%) if the non-specific (NOS) disorders were excluded. The most common diagnostic groups were affective disorders (8.6%, 7.9%-9.5%), anxiety disorders (4.3%, 3.6%-5.1%), and substance use disorders (3.0%, 2.4%-3.8%). The most common specific disorders were major depressive disorder (4.3%, 3.7%-4.9%), alcohol use disorder (2.9%, 2.3%-3.7%), dysthymia (1.6%, 1.3%-1.9%) and specific phobias (1.2%, 0.8%-1.8%). The overall prevalence was higher in rural than in urban areas (RR = 1.23, 95% CI = 1.11-1.37) and slightly higher in women than in men (RR = 1.11, 1.00-1.22).</p><p><b>CONCLUSIONS</b>Mental disorders seriously affect the social and economic development of Zhejiang Province; they are a major public health problem that urgently needs to be addressed. To do this, it is necessary to develop and implement a comprehensive province-wide mental health plan and regularly evaluate its effectiveness.</p>