Medical Outcomes Study, 1986-1992
The Medical Outcome Study, 1986-1992 (MOS) is a large-scale multiyear survey of patients with prevalent and treatable chronic health conditions, particularly hypertension, heart disease, diabetes, and depression. A cross-sectional component describes the impact of chronic diseases on patient well-being as well as the medical care that patients received. A longitudinal component illustrates changes in health conditions over time and covers outcomes in terms of care, provider specialty, style of practice, and other factors that influence utilization of health care resources. Investigators at Rand employed a variety of assessment instruments, such as self-administered questionnaires for patients and clinicians, face-to-face interviews, telephone interviews, clinical reports, and health examinations. The SF-36 health survey was administered longitudinally to measure important health and functioning domains. The MOS marked several methodological advances: (1) measurement of three dimensions of health status in parallel, initially and longitudinally; (2) a focus on patients' own personal evaluation of their functional status and well-being-to better address the needs of patient-based assessments of medical outcomes; and (3) the use of both standardized patient surveys and clinical evaluations as measures of health status. The MOS was the first large-scale study in which patients with different medical and psychiatric conditions completed the same self-administered questionnaires. The study samples were drawn from patients receiving health care from practices in Boston, Chicago, and Los Angeles. Thirty-five cross-sectional and two longitudinal data files have been combined in a single data file with 4,533 variables and 23,097 cases.