Fauser David, Bethge Matthias
Institut für Sozialmedizin und Epidemiologie, Sektion Rehabilitation und Arbeit, Universität zu Lübeck.
Rehabilitation (Stuttg). 2019 Feb;58(1):50-58. doi: 10.1055/a-0781-8967. Epub 2019 Feb 15.
The randomized controlled trial is the gold standard to validate the efficacy of an intervention. Randomized treatment assignment in intervention and control group independent of patient characteristics or previous measures of patient care allows one to estimate unbiased treatment effects. Differences in outcomes can be attributed causally to the treatment. In observational studies treatment assignment is not randomized in intervention and control group. Instead, the assignment is influenced by patient characteristics. This could lead to biased estimates of treatment effects. Statistical approaches based on the propensity score take into account the group differences in observational data. The propensity score is the probability of treatment assignment conditional on observed variables. By means of propensity-score-matching balanced samples of treated and control subjects can be formed. To express treatment effects, the same statistical approaches can be used as those in randomized controlled trials.
随机对照试验是验证一种干预措施疗效的金标准。干预组和对照组的随机治疗分配独立于患者特征或先前的患者护理措施，这使得人们能够估计无偏的治疗效果。结果的差异可以因果归因于治疗。在观察性研究中，干预组和对照组的治疗分配不是随机的。相反，分配受到患者特征的影响。这可能导致对治疗效果的估计有偏差。基于倾向评分的统计方法考虑了观察数据中的组间差异。倾向评分是基于观察变量的治疗分配概率。通过倾向评分匹配，可以形成治疗组和对照组的平衡样本。为了表达治疗效果，可以使用与随机对照试验相同的统计方法。
