Mental health is one's state of well-being that enables the person to display his/her abilities, to cope with daily stress, to work productively and to contribute to community. Mental health in such a positive sense becomes the base of well-being and effective roles for individuals and community. In a positive sense, mental health may involve both health and diseases and, accordingly, everybody desires mental health and feels subjective health regardless of whether he/she has a mental disorder.⁴

Health indicators are scales not only on the health status of a population group but also on the general level or characteristic of all relevant items including health policy, healthcare system, healthcare resource, natural environment, size and composition of population, and people's perception and value of health.⁵ That is, they express the quantitative and qualitative aspects of health by comprehensively indicating systems and statuses related to a population group's health promotion and prevention of diseases.⁶

Accordingly, 'mental health indicators,' which combines the two concepts, are scales showing people's mental disorders as well as their positive mental health including subjective wellbeing and expressing the quantitative and qualitative state of policies and services promoted to solve mental health problems, to promote mental health and to prevent mental disorders. That is, these indicators are used to measure various aspects of mental health system like population groups' need of mental health services (e.g., the percentage of population belonging to vulnerable groups), resources invested in mental health service systems (e.g., the number of mental health professionals per 100,000 persons, and the percentage of budgets for mental health promotion programs in budgets for general health promotion), quality of service activities including the ways of delivering protection (e.g., the annual number of mental inpatients per 100,000 persons), and the effect of mental health services in service consumers (e.g., annual suicide rate, symptom reduction, disability level, quality of life).⁷

Recently, several international organizations promoted indicator development projects. The Organisation for Economic Co-operation and Development (OECD) conducted the Health Care Quality Indicators Project, through which it defined mental health as one of the five priority areas, reviewed indicators in the member countries, and developed internationally comparable indicators on the quality of mental health.⁸ WHO performed a indicator development project for evaluating mental health policies and services usable in underdeveloped countries in order to solve the problem that over 24% of 202 areas, including the member states, associated members, territories, and areas, did not have systems for collecting and reporting mental health information and that mental health evaluation and monitoring tools used in developed countries are not applicable to developing and underdeveloped countries in terms of objective, scope, structure and contents.⁹ The European Union (EU) also promoted the Mental Health Information and Determinants for the European Level (MINDFUL) project based on previous projects for improvement in mental health information and comparison among its member countries with the object of expanding the scope of mental health monitoring systems so that they comprehend not only negative mental health but also positive mental health, mental health promotion, and mental disorder prevention.¹⁰

Among individual countries, the U.S., Australia, the U.K., Scotland, etc. have developed indicators in order to monitor the performance and services of mental health. The U.S. developed indicators on the performance of mental health services to meet consumers' needs actively,¹¹ and Australia developed indicators on the performance of mental health services in public sectors in connection to the strategic directions of national mental health plans and characteristically it included indicators related to safety.¹² In the U.K., mental health indicators have been used in evaluating the performance of the Mental Health Trust since 2001,¹³ and the indicators were designed jointly by the government, the Commission for Health Improvement, and the Ministry of Health. Developed indicators aim to help people understand the performance of community health services and to provide information easily and conveniently, and every year new indicators are developed in the process of setting the goals of the National Health Service in order to reflect changes timely and evaluate performance properly.¹⁴ Scotland gives national priority to mental health promotion and promotes national visions such as people's mental health, quality of life, welfare, and social integration of those with mental disorders or mental health problems. Moreover, it has defined the concept of mental health in two aspects, namely, mental health problems such as anxiety and positive mental health such as satisfaction with life and positive relations with others, and developed mental health indicators focusing on the measurement of positive mental health.¹⁵ Table 1 summarizes the current state of indicator development in international organizations and major countries as presented above.

The characteristics of mental health indicator development in foreign countries are as follows. First, the objectives of mental health indicator development reflect each country's national mental health strategies and aim at measuring and monitoring the performance of current national mental health policies for mental health promotion. In case of international organizations, indicators are developed mainly to compare the quality of mental health among countries. Second, most countries are making efforts to build up a comprehensive frame including the performance of mental health policies, the provision of services, each population group's current mental health status, etc. in order to measure the performance of mental health services. Third, the concept of mental health is being expanded so that it connotes not only mental disorders but also personal protection factors of positive mental health such as resilience, self-esteem and self-efficacy. Fourth, with regard to the contents of indicators, consumers' viewpoint emphasizing consumers' experience in provided mental health services is being introduced in addition to the current state of mental health like mental disorders and the contents of mental health services. Introducing these kinds of indicators will contribute to changing mental health services consumer-centered. Fifth, indicator systems for inter-regional comparison and frameworks for standardized measurements are being developed. Sixth, the development of mental health indicators does not take place in a short period but goes through long-term refinement and revision.

This study attempted to develop indicators that reflect the current state of mental health in Korea, the objectives of national policies and people's needs of mental health, and are internationally comparable. In addition, indicators were developed with the object of enhancing quality of mental health, improving mental health facilities and personnel, upgrading the quality of mental health service, respecting the human rights of people with mental disorders, and using limited mental health resources efficiently and effectively.

For the development of mental health indicators in Korea, we made an effort to include mental health indicators of Health Plan 2010¹⁶ and the National Mental Health Commission report¹⁷ (Table 2). Health Plan 2010 was a national plan intended to improve the accessibility of mental health service, the level of national mental health and the quality of life of people with mental disorders. The National Mental Health Commission developed some indicators to assess community mental health services.

In developing indicators, we focused on adults and the scope of indicators comprehended mental health problems including mental disorders, resources including manpower, facilities and finance, mental health services, risk and protection factors, etc. Moreover, the scope of mental health services was divided into five domains, that is, mental health status, mental health factor, mental health system, mental health service, and the quality of mental health services so that it includes prevention, treatment, continuous management and early interventions, and divided again into 21 subdomains according to the nature of indicators (Table 3).

'Mental health status' covers positive mental health and mental health problems including mental disorders, and 'mental health factor' covers personal factors and environmental factors that may affect mental health. 'Mental health system' includes indicators related to mental health resources and covered policies and plans related to mental health, organizations and human resources involved in mental health services, and budgets and finance. 'Mental health service' comprehends all mental health activities conducted in the area of mental health including services for the prevention, treatment, and rehabilitation of mental disorders, and 'Quality of mental health' includes indictors to measure whether mental health services enhance the level of mental health and whether such services are provided based on evidence.

By reviewing indicators developed in Korea and major foreign countries presented above, we collected around 600 indicators. Then, in consideration of their redundancy and availability, the principles of indicator development in this study, and the indicator system, we reduced them into 22 indicators on mental health status, 8 on mental health factor, 29 on mental health system, 38 on mental health service and 27 on the quality of mental health services, so a total of 124 indicators in the 1st questionnaire.

We conducted the 1st and 2nd questionnaire surveys with experts recommended by academic societies related to mental health in Korea. In detail, we recruited 19 participants who have expertise in the area under investigation from the following societies: Korean Neuropsychiatric Association, Korean Society of Clinical Psychology, Korean Association of Mental Health Social Workers, and Korean Academy of Psychiatric and Mental Health Nursing.

The purpose of the surveys was to collect the experts' opinions on the fitness of mental health indicators developed by the authors. Based on the results of the 1st questionnaire survey, the 2nd questionnaire was developed through adding new indicators and revising the terms of indicators. The 1st questionnaire survey presented each expert indicator categories and 124 indicators developed by the authors, and had them rate the importance of each indicator domain/subdomain and item on a 5-point scale. Then, the importance of the indicator categories and items was assessed by the mean score and the proposed indicators were revised.

In the results of the questionnaire survey on the suitability of indicator category, adequacy was high in order of mental health system, mental health service, mental health status, the quality of mental health services, and mental health factor among the 5 higher domains. Among the subdomains, those belonging to mental health system such as policies and plans, organizations, finance, and human resource, and those belonging to mental health service such as early interventions, treatment and rehabilitation attained a high score, showing high consistency with the results on the fitness of the 5 higher domains. In the questionnaire for assessing the importance of individual indicators, 40 out of the 124 indicators got a mean score of 4 or higher.

We developed the 2nd questionnaire containing a total of 127 indicators by revising terms and adding new indicators based on experts' opinions collected in the 1stt questionnaire survey. The 2nd questionnaire survey presented the results of the 1st survey and the revised questionnaire. As in the 1st questionnaire survey, the respondents rated the importance of each indicator category and item at a 5-point-scale, and then the fitness and importance of the indicator categories and individual indicators were assessed by the mean score. In the 2nd questionnaire survey, the suitability of mental health system and mental health services was also rated high and this result was mostly consistent with the results on the subdomains. To put it concretely in the results on the subdomains, 'policies and plans,' 'organizations,' 'human resources' and 'finance' belonging to mental health system, and 'early interventions' and 'treatment' belonging to mental health service showed high importance (Table 3).

In the results of expert survey on individual indictors, the number of indicators scoring 4 or higher was 59 out of 127, which was 19 larger than that in the 1st survey. Among the top 30 indicators based on the mean score, 10 belonged to 'mental health system' and this is considered to suggest the importance of resources such as policies, organizations, human resources and finance in understanding the current situation of mental health and making related policies in Korea. Moreover, indicators in the subdomain of 'mental health problem' ranked high. In particular, 'suicide rate' ranked first probably because of the rapidly increasing number of suicides. Besides, the annual prevalence of mental disorders, depression and alcoholism was found to be an important indicator. It is also considered necessary to measure social and economic burdens caused by mental disorders including socioeconomic expenses resulting from mental disorders and suicides (Table 4).