Associations of serious mental illness with earnings: results from the WHO

burden is now well established both in terms of disability-adjusted life-years and as a fraction of national budgets. A large part of this burden consists of indirect costs such as those associated with reduced rates of labour force participation, unemployment among those in the labour force and underemployment among those who are employed. Mental disorders also have costs for employers, including high rates of sporadic absenteeism and disability-related work leave as well as low levels of on-the-job work performance. The most commonly used approach to study these labour market costs is the human capital approach. This approach is based on the observation that wages and salaries are paid in direct return for productive services, making earnings a good indicator of the human capital accumulated by the individual and making earnings-equivalent time forgone because of an illness a good representation of the indirect costs of that illness to the employer. Although a considerable body of empirical research has used the human capital approach to document adverse societal effects of mental disorders, this research has been carried out largely in a small number of high-income countries. Yet epidemiological data show that mental disorders are common throughout the world. The purpose of the current paper is to use the survey data in the World Health Organization (WHO) World Mental Health (WMH) Surveys to make estimates of the human capital costs of mental disorders in a wider range of countries (population samples from 10 high-income and 9 lowand middle-income countries with a total of more than 100 000 respondents). We focus on serious mental illness because previous research has shown that earnings and long-term work incapacity are both much more strongly related to serious mental illness than to less serious forms of mental illness.