Mp. Fay et Ej. Feuer, CONFIDENCE-INTERVALS FOR DIRECTLY STANDARDIZED RATES - A METHOD BASEDON THE GAMMA-DISTRIBUTION, Statistics in medicine, 16(7), 1997, pp. 791-801
We offer an approximation to central confidence intervals for directly
standardized rates, where we assume that the rates are distributed as
a weighted sum of independent Poisson random variables. Like a recent
method proposed by Dobson, Kuulasmaa, Eberle and Scherer, our method
gives exact intervals whenever the standard population is proportional
to the study population. In cases where the two populations differ no
n-proportionally, we show through simulation that our method is conser
vative while other methods (the Dobson et al. method and the approxima
te bootstrap confidence method) can be liberal. (C) 1997 by John Wiley
& Sons, Ltd.