Compara mètodes

	Abridged Life Table	Indirect Age Standardization
Camp	Social Epidemiology	Social Epidemiology
Família	Process / pipeline	Process / pipeline
Any d'origen	1984	2001
Autor original	Chin Long Chiang; Samuel Preston, Patrick Heuveline & Michel Guillot	Classical demography / vital statistics (formalized in Preston, Heuveline & Guillot)
Tipus	Demographic estimation pipeline for mortality and survivorship	Rate-standardization pipeline for comparing populations under unstable stratum rates
Font seminal	Chiang, C. L. (1984). The Life Table and Its Applications. Malabar, FL: Robert E. Krieger Publishing. ISBN: 9780898745702	Preston, S. H., Heuveline, P., & Guillot, M. (2001). Demography: Measuring and Modeling Population Processes. Blackwell Publishers. ISBN: 9781557864512
Àlies	Abridged Life Table Method, Grouped-Age Life Table, Chiang Life Table, nMx to nqx Life Table	Indirect Standardization, Standardized Mortality Ratio (SMR), Indirectly Standardized Rate, SMR Method
Relacionats	3	3
Resum	The abridged life table is the workhorse of demography and population health for summarizing the mortality experience of a population in a single, age-grouped table. Instead of a single-year (complete) life table, it works on broad age intervals — typically <1, 1-4, then five-year groups up to an open-ended oldest interval — which makes it robust when deaths or populations in single years of age are sparse or noisy. The construction propagates a small set of inputs, the age-specific death rates nMx, through a chain of columns: the probability of dying nqx, the survivors lx, the deaths ndx, the person-years lived nLx and Tx, and finally life expectancy ex. Chiang's 1984 treatment supplied the standard estimator and the fraction-of-interval term ax that controls how person-years are allocated within each interval, while Preston, Heuveline and Guillot's 2001 textbook codified the modern pipeline used across demography and epidemiology.	Indirect age standardization is a demographic technique for comparing the overall event rate (most often mortality) of a study population to a reference, when the population's own age-specific rates are too sparse or unstable to standardize directly. Instead of applying the study population's rates to a standard age structure, it does the reverse: it applies a stable set of standard age-specific rates to the study population's age distribution to compute the number of events that would be expected under the standard schedule. The ratio of observed to expected events is the standardized mortality (or morbidity) ratio, the SMR, and multiplying it by the standard's crude rate yields an indirectly standardized rate. The method is a staple of vital statistics and occupational and small-area epidemiology, and is developed from first principles in Preston, Heuveline and Guillot's demography text.