CONTROLLING FOR TIME-SINCE-HIRE IN OCCUPATIONAL STUDIES USING INTERNAL COMPARISONS AND CUMULATIVE EXPOSURE

被引:18
作者
ARRIGHI, HM [1 ]
HERTZPICCIOTTO, I [1 ]
机构
[1] UNIV N CAROLINA,SCH PUBL HLTH,DEPT EPIDEMIOL,CHAPEL HILL,NC
关键词
EPIDEMIOLOGIC METHODS; BIAS; COHORT STUDIES; OCCUPATIONAL EXPOSURES; TIME-RELATED FACTORS; MODELS;
D O I
10.1097/00001648-199507000-00015
中图分类号
R1 [预防医学、卫生学];
学科分类号
1004 ; 120402 ;
摘要
Employees within an occupational cohort may demonstrate a more favorable mortality experience while maintaining employment than those who leave employment. At the same time, they may experience an apparent decline in health with time-since-hire. The time-since-hire effect may occur independently of exposure but may nevertheless result in groups categorized by cumulative exposure that are not comparable. Controlling for time-since-hire appears to solve this problem. To quantify the empirical bias in estimates of exposure effect due to confounding from time-since-hire, we analyzed two occupational cohorts using Poisson regression with and without ad adjustment for time-since-hire or time-since-start-of-follow-up. In a cohort exposed to airborne arsenic, a strong dose-response relation with respiratory cancer mortality had been established: In a cohort exposed to external, penetrating ionizing radiation, a weak and controversial dose-response relation had been reported. The parameter estimates relating exposure to disease from the models that explicitly adjusted for time-since-hire or time since-start-of-follow-up are within 10% of the estimates from models that did not. It appears, from this empirical analysis of two datasets, that occupational studies may not need to adjust explicitly for such time-related factors as time-since-hire or time-since-start-of-follow-up if these are implicitly controlled through other variables in the model.
引用
收藏
页码:415 / 418
页数:4
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