قارن الطرق

	Active Life Expectancy Estimation	Healthy Life Expectancy
المجال	Social Gerontology	علم السكان
العائلة	Survival analysis	Survival analysis
سنة النشأة	1983	1971
صاحب الطريقة	Sidney Katz, Laurence G. Branch and colleagues	Daniel F. Sullivan (Sullivan method); developed by the WHO/REVES tradition
النوع	Life-table estimator partitioning remaining life into active and dependent years	Health-expectancy estimator partitioning life expectancy into healthy and unhealthy years
المصدر التأسيسي	Katz, S., Branch, L. G., Branson, M. H., Papsidero, J. A., Beck, J. C., & Greer, D. S. (1983). Active life expectancy. New England Journal of Medicine, 309(20), 1218-1224.	Sullivan, D. F. (1971). A single index of mortality and morbidity. HSMHA Health Reports, 86(4), 347–354.
الأسماء البديلة	ALE, Disability-Free Years Expectancy, Independent Life Expectancy, Active vs Dependent Life Years	HALE, Health-Adjusted Life Expectancy, Disability-Free Life Expectancy
ذات صلة	4	4
الملخص	Active life expectancy (ALE) estimates how many of an older person's remaining years are expected to be lived in an active, independent state — free of disability in basic activities of daily living — as opposed to a dependent state requiring help. Introduced by Sidney Katz, Laurence Branch, and colleagues in 1983 in the New England Journal of Medicine, it answered a question that ordinary life expectancy cannot: not just how long people live, but how much of that life is lived in good functional health. The method combines age-specific mortality with the prevalence or transitions of ADL disability within a life-table framework, partitioning total remaining life into active and dependent components that sum to overall life expectancy. Katz and colleagues showed, using data from older adults in Massachusetts, that active life expectancy declines faster than total life expectancy with age and differs across groups. The concept reframed the goal of aging policy from merely extending lifespan to extending the active, independent portion of it. It launched the broader field of health expectancy measures and remains foundational to studying the compression or expansion of late-life morbidity.	Healthy life expectancy partitions ordinary life expectancy into the years a person can expect to live in good health and the years expected to be lived with disability or ill health. Building on the life table, the classic Sullivan method weights each age interval's person-years by the prevalence of good health, so the resulting expectancy answers not just 'how long will people live?' but 'how many of those years will be healthy?'. It has become a headline summary of population health, reported by the World Health Organization as HALE and tracked alongside life expectancy to judge whether longer lives are also healthier lives.