samples derived from cross-sectional surveys and provide only basic measures of activity limitation. Because most health and social service programs are coordinated at the state level, the lack of state-specific data hampers planning of services. Existing data systems are insensitive to changes in the prevalence of impairment and disability over time, and they do not measure the degree of limitation and disability that results from specific chronic diseases and mental illnesses, also undermining planning of prevention strategies.
Data collection reflects this nation's emphasis on acute care. It is episodic, and fixed on single points in time. In contrast, chronic diseases, by definition, are long-term conditions, and their impacts change over time.
Surveillance methods do not permit us to track the series of changes in health status, functional capacity, and quality of life that people with chronic disease are likely to experience. National and state systems of surveillance of disabling conditions should be refined so