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不朽的时间偏差与时间变化的暴露在环境流行病学:肺癌存活率的案例研究
American journal of epidemiology
|July 4, 2023
概括
不朽的时间偏差是临床研究中常见的问题,可能会影响环境流行病学研究. 这项研究表明,在随访期间平均空气污染暴露可以膨胀风险估计,而非离散时间方法,使暴露与随访开始保持一致.
科学领域:
- 环境流行病学环境流行病学
- 临床流行病学临床流行病学
- 生物统计学 生物统计学
背景情况:
- 不朽的时间偏差在临床流行病学中得到认可,但在环境流行病学中没有得到充分讨论.
- 这种偏差来自于研究后续开始 (时间0) 和暴露/治疗分配之间的错位.
- 环境暴露的时间趋势可能会加剧这种偏差.
研究的目的:
- 调查不朽时间偏差在环境流行病学中的影响.
- 为了比较暴露的平均值与评估颗粒物 (PM2.5) 和肺癌风险的离散时间方法.
- 突出调整暴露评估与目标试验框架的重要性.
主要方法:
- 从加利福尼亚癌症登记处 (2000-2010年) 使用的肺癌病例.
- 链接的注册表数据与细颗粒物物质 (PM2.5) 的估计度.
- 对比了一个时间到事件模型,平均PM2.5在随访期间,与一个离散时间模型对应暴露时间为0.
主要成果:
- 平均PM2.5暴露给出了1.38的危险比率 (95% CI: 1.36, 1.40) 对于5μg/m3的增加.
- 离散时间方法产生了0.99 (95%CI:0.98,1.00) 的聚合几率比率.
- 平均方法的膨胀风险估计归因于不朽的时间偏差.
结论:
- 不朽的时间偏差可以显著扭曲环境流行病学中的发现,当暴露在随访期间的平均值.
- 离散时间方法,将暴露与随访开始对齐,提供更准确的风险估计.
- 在目标试验框架内对时间变化的环境暴露进行适当的概念化对于防止系统性错误至关重要.
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