Reducing healthy worker survivor bias by restricting date of hire in a cohort study of Vermont granite workers
Reducing healthy worker survivor bias by restricting date of hire in a cohort study of Vermont granite workers
复制标题
DOI：
10.1136/oem.2006.031369
复制
发表时间：
2007-10-01
影响因子：
4.9
通讯作者：
Eisen, Ellen A.
中科院分区：
文献类型：
--
作者：
Applebaum, Katie M.;Malloy, Elizabeth J.;Eisen, Ellen A.
目的：在佛蒙特州花岗岩工人的研究中，通过在随访开始之前或之后根据雇用日期区分“普遍”和“意外”雇用，探讨健康工人幸存者效应（HWSE）。方法：从医学监测项目中获得1950年至1982年工人的记录。比例风险模型用于模拟二氧化硅暴露与肺癌死亡率之间的关系，惩罚样条用于平滑暴露-反应关系。敏感度分析比较了原始队列和通过限制雇用日期以包括不同比例的流行雇用来定义的子队列之间的结果。结果：限制事故雇用减少了213例，减少了74%，减少了暴露范围。在所有亚群中，最大死亡率比（MRR）接近2倍。然而，达到最大MRR的暴露量从4.0毫克-年/米下降到0.6毫克-年/米(3)，因为普遍雇佣的比例从原始队列的50%下降到事件雇佣亚队列的0%。结论：尽管功率下降和暴露范围受限，但降低普遍雇佣和意外雇佣的相对比例减少了HWSE偏差，从而为二氧化硅暴露和肺癌死亡率之间的剂量反应提供了更有力的证据。
Objective: To explore the healthy worker survivor effect (HWSE) in a study of Vermont granite workers by distinguishing "prevalent'' from "incident'' hires based on date of hire before or after the start of follow-up.Methods: Records of workers between 1950 and 1982 were obtained from a medical surveillance programme. Proportional hazards models were used to model the association between silica exposure and lung cancer mortality, with penalised splines used to smooth the exposure-response relationship. A sensitivity analysis compared results between the original cohort and subcohorts defined by restricting date of hire to include varying proportions of prevalent hires.Results: Restricting to incident hires reduced the 213 cases by 74% and decreased the exposure range. The maximum mortality rate ratio (MRR) was close to twofold in all subcohorts. However, the exposure at which the maximum MRR was achieved decreased from 4.0 to 0.6 mg-year/m(3) as the proportion of prevalent hires decreased from 50% in the original cohort to 0% in the subcohort of incident hires.Conclusion: Despite loss in power and restricted exposure range, decreasing the relative proportion of prevalent to incident hires reduced HWSE bias, resulting in stronger evidence for a dose-response between silica exposure and lung cancer mortality.