在观察性研究中的偏见和因果关系
David A Grimes1, Kenneth F Schulz
1Family Health International, PO Box 13950, Research Triangle Park, NC 27709, USA. dgrimes@fhi.org
Lancet (London, England)
|January 29, 2002
概括
了解内部和外部有效性对于医学研究至关重要. 本摘要解释了如何识别和减轻偏见,如选择,信息和混,以确保准确的研究结果.
科学领域:
- 流行病学 流行病学
- 医学研究方法学 医学研究方法学
背景情况:
- 医学文献的解释需要评估内部和外部有效性.
- 内部有效性确保研究衡量其预期结果.
- 外部有效性涉及研究结果对患者群体的概括性.
研究的目的:
- 定义和区分医学研究中的有效性关键概念.
- 概述观察性研究中偏见的常见来源.
- 提供控制混和评估因果关系的方法.
主要方法:
- 讨论内部有效性威胁:选择偏见,信息偏见和混.
- 偏差类型的解释:差异和非差异错误分类.
- 混控制策略的概述:限制,匹配,分层和多变量技术.
主要成果:
- 选择偏差来自于非可比的群体.
- 信息偏差是由于不准确的曝光或结果确定导致的.
- 当第三个因素扭曲暴露与结果关系时,会发生混.
结论:
- 在考虑机会之前,读者必须批判性地评估研究的潜在偏见.
- 评估时间序列,关联强度和剂量反应等标准支持因果推断.
- 区分虚假,间接和因果关联对于有效的医学结论至关重要.
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