Prevalence of mental disorders in China – Author's reply

On behalf of my coauthors, I thank Yu-Tao Xiang and colleagues and Chuanyuan Kang and Jianzhong Yang and colleagues for their comments on our Article.1Lu J Xu X Huang Y et al.Prevalence of depressive disorders and treatment in China: a cross-sectional epidemiological study.Lancet Psychiatry. 2021; 8: 981-990Summary Full Text Full Text PDF PubMed Scopus (9) Google Scholar In response to Xiang and colleagues, all surveys that are part of the World Mental Health Survey,2Kessler RC Bedirhan Ustun T The WHO world mental health surveys - global perspectives on the epidemiology of mental disorders. Cambridge University Press, 2008Google Scholar including the China Mental Health Survey, use Composite International Diagnostic Interview (CIDI) to assess 30-day prevalence and 12-month prevalence. The two terms are different from point prevalence and 1-year prevalence. The use of 30-day and 12-month prevalence is an advance in the epidemiological investigation methods of mental disorders. In a large-scale population survey, it is difficult to conduct fieldwork on a single day as a time point, and to complete a whole survey in one calendar year. Therefore, in the China Mental Health Survey, we recorded prevalence duration from the interview day to any time in the past 12 month as 12-month prevalence and “have ever” as lifetime prevalence. Because some disorders cannot be diagnosed within 30 days, 30-day prevalence is seldom applied in most surveys using CIDI. Xiang and colleagues mentioned that the specificity of CIDI 3.0 for major depressive disorder was only 68·6% and for dysthymia it was 72·3%.3Huang YQ Xie SF Lu J et al.Community-based evaluation of the reliability and validity of Chinese version of Composite International Diagnostic Interview-3.0.Chin Ment Health J. 2010; 24 (in Chinese).: 21-24Google Scholar In the same paper, we reported the sensitivity of CIDI 3.0 for detecting major depressive disorder was 91·2% and for dysthymia it was 86·2%.3Huang YQ Xie SF Lu J et al.Community-based evaluation of the reliability and validity of Chinese version of Composite International Diagnostic Interview-3.0.Chin Ment Health J. 2010; 24 (in Chinese).: 21-24Google Scholar This shows that CIDI 3.0 is an effective tool to screen for major depressive disorder and dysthymia, because it has high sensitivity. By contrast, a diagnostic tool should have high specificity. As for the low rate of treatment in the China Mental Health Survey,1Lu J Xu X Huang Y et al.Prevalence of depressive disorders and treatment in China: a cross-sectional epidemiological study.Lancet Psychiatry. 2021; 8: 981-990Summary Full Text Full Text PDF PubMed Scopus (9) Google Scholar we believe this was due to the low reporting rate of the respondents and stigma preventing patients from seeking help from psychiatrists. Mental health among migrant workers is an important field, but was not an aim of the China Mental Health Survey. To our knowledge, there is no evidence that prevalence of depressive disorder in migrants is higher than in other population groups in China. Therefore, excluding migrant workers does not mean underestimation of the prevalence of depressive disorder in the country as a whole. The Quick Inventory of Depressive Symptomatology in CIDI 3.0 was modified for the World Mental Health Survey to assess severity of depressive symptoms for patients with 12-month prevalence rather than to diagnose depressive disorder. A single interview covered symptoms in the past 12 months and over the lifetime, detailed assessment of clinical severity, and information on treatment, risk factors, and consequences.4Kessler RC Bedirhan UstÜn T The World Mental Health (WMH) survey initiative version of the World Health Organization (WHO) Composite International Diagnostic Interview (CIDI).Int J Methods Psychiatr Res. 2006; 13: 93-121Crossref Scopus (2963) Google Scholar In the China Mental Health Survey, local lay interviewers recruited from the sampling points in 31 provinces and trained using an international standardised training programme could accurately complete CIDI for local people. A series of papers from the World Mental Health Survey have shown that CIDI 3.0 has wide cultural applicability in more than 30 countries, including China. The low report rate of depressive disorder in China for poorly educated respondents and patients who tend to somatise their depressive symptoms is something that we have repeatedly expounded. However, in the China Mental Health Survey, we have to ask the same questions as in the World Mental Health Survey to make internationally cross-cultural comparisons. The prevalence of depressive disorders in the whole study sample was reported in our earlier paper.5Huang Y Wang Y Wang H et al.Prevalence of mental disorders in China: a cross-sectional epidemiological study.Lancet Psychiatry. 2019; 6: 211-224Summary Full Text Full Text PDF PubMed Scopus (530) Google Scholar The China Mental Health Survey cannot be compared with the two surveys in 1982 and 1993 and other past regional surveys because of development and improvement in the survey methodology. Kang and Yang point out that no national data on mental disorders in children and adolescents are available in China. They cited 17·5% as the prevalence of any mental disorder from a survey on children and adolescents in five provinces in China.6Fenghua Li Yonghua Cui Ying Li et al.Prevalence of mental disorders in school children and adolescents in China: diagnostic data from detailed clinical assessments of 17,524 individuals.J Child Psychol Psychiatry. 2021; (published online May 21.)https://doi.org/10.1111/jcpp.13445Google Scholar This survey was done only in schools because of funding constraints. Differences exist between children and adolescents and adults in both diagnosis and treatment for mental disorders. Hence, it would be very difficult for a large-scale community survey to include children, adolescents, and adults in all age groups, from a survey design and from a financial point of view. Psychiatrists in China are striving for more resources to conduct nationwide surveys in children and adolescents. There are few extensive national surveys on mental disorders in individuals younger than 18 years from anywhere in the world. Kang and Yang also noted that few surveys on mental disorders in China include people from ethnic minorities, even though there are 56 ethnic minorities in China with quite different cultural diversity, accounting for 8·89% of the total population. Doing questionnaire surveys in areas with multiple ethnic groups is a challenge for all in the psychiatric field.2Kessler RC Bedirhan Ustun T The WHO world mental health surveys - global perspectives on the epidemiology of mental disorders. Cambridge University Press, 2008Google Scholar To date, few surveys in ethnic groups have shown lower prevalence among other ethnic groups than in Han Chinese individuals.7Lu W Hunag Y-Q Luo C et al.A cross-sectional study of mental disorders in Ximeng Wa Autonomous County of Yunnan Province.Chin Ment Health J. 2015; 29 (in Chinese).: 817-825Google Scholar Our psychiatric epidemiologists have much to explore and study. I declare no competing interests Prevalence of depressive disorders and treatment in China: a cross-sectional epidemiological studyDepressive disorders in China were more prevalent in women than men, unemployed people than employed, and those who were separated, widowed, or divorced than people who were married or cohabiting. Most people with depressive disorders reported social impairment. Treatment rates were very low, and few people received adequate treatment. National programmes are needed to remove barriers to availability, accessibility, and acceptability of care for depression in China. Full-Text PDF Prevalence of mental disorders in ChinaThe Article published by Jin Lu, Xiufeng Xu, and colleagues1 in The Lancet Psychiatry on the prevalence of depressive disorders in China has attracted much interest. Due to several methodological issues, we believe that the findings should be interpreted with caution. Full-Text PDF Prevalence of mental disorders in ChinaJin Lu, Xiufeng Xu and colleagues described the socioeconomic characteristics and use of mental health services in people with depressive disorders in China, using data from the China Mental Health Survey (2012–15).1 These are the first nationwide data on the epidemiology, clinical severity, functional impairment, and treatment of depressive disorders in the general population in China, which can be used to plan the prevention and treatment of depressive disorders. Full-Text PDF