Evidence from non-randomized and partially randomized studies (N: Non-randomized)

随机对照试验（rct）被认为是临床试验中比较治疗方法的金标准。然而，由于各种原因，关于观察性或部分随机研究证据的讨论仍然是当前的主题。在某些情况下，随机化是不可能的、不可行的或不可执行的。另一个论点涉及外部有效性。虽然随机分配治疗确保治疗比较的内部有效性，但外部有效性的评估最好通过将随机研究样本与不同意随机化但符合所有其他资格标准的患者人群进行比较来实现。这些考虑导致了Cochrane协作组“非随机研究方法组”的成立，其主要任务是为在系统评价中纳入非随机研究提供指导。这表明该领域的研究是有必要的。在缺乏随机对照试验证据的情况下，从非随机或部分随机研究中寻找证据是很自然的。在这个项目中，我们一方面侧重于评估从这些研究中获得证据的方法，另一方面侧重于开发创新的统计方法，特别强调其实际适用性。

Randomized controlled trials (RCTs) are regarded to be the gold standard for the comparison of treatments in clinical trials. Nevertheless, the discussion about evidence from observational or partially randomized studies is still a current topic for various reasons. In some situations a randomization is not possible, feasible, or not enforceable. Another argument concerns the external validity. While a random assignment to treatment ensures internal validity of the comparison of the treatments, an assessment of external validity can best be achieved by comparing the randomized study sample to the population of patients who did not consent to randomization but met all other eligibility criteria. These considerations have led to the foundation of the 'Non-randomized Studies Methods Group' of the Cochrane Collaboration whose main task is the production of guidance on the inclusion of non-randomized studies in systematic reviews. This shows that research in this area is indicated. In the absence of evidence from RCTs it is natural to seek evidence from non-randomized or partially randomized studies. In this project, we focus on the one hand on the assessment of approaches introduced to gain for evidence from such studies and on the other hand on the development of innovative statistical methods with special emphasis on their practical applicability.