BACKGROUND In the last years, there has been an increase in publication of systematic reviews of normative ("argument-based") literature or of normative information (such as ethical issues) in bioethics. The aim of a systematic review is to search, select, analyse and synthesise literature in a transparent and systematic way in order to provide a comprehensive and unbiased overview of the information sought, predominantly as a basis for informed decision-making in health care. Traditionally, one part of the procedure when conducting a systematic review is an appraisal of the quality of the literature that could be included. MAIN TEXT However, while there are established methods and standards for appraising e.g. clinical studies or other empirical research, quality appraisal of normative literature (or normative information) in the context of a systematic review is still rather a conundrum - not only is it unclear how it could or should be done, but also the question whether it necessarily must be done is not settled yet. Based on a pragmatic definition of "normative literature" as well as on a typology of different types of systematic reviews of normative literature/information, this paper identifies and critically discusses three possible strategies of conducting quality appraisal. CONCLUSIONS The paper will argue that none of the three strategies is able to provide a general and satisfying solution to the problems associated with quality appraisal of normative literature/information. Still, the discussion of the three strategies allows outlining minimal conditions that elaborated strategies have to meet in future, and facilitates sketching a theoretically and practically promising strategy.

中文翻译：

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在规范性文献/信息的系统评价中，如何解决质量评估难题？分析三种可能策略的问题（德文翻译）。

背景技术在过去的几年中，对生物伦理​​学中的规范性（基于“论据”的）文献或规范性信息（例如伦理学问题）进行系统评论的出版物有所增加。系统评价的目的是以透明，系统的方式搜索，选择，分析和综合文献，以便对所寻求的信息提供全面而公正的概述，主要作为医疗保健中明智决策的基础。传统上，进行系统审查时，程序的一部分是对可能包括在内的文献质量的评估。正文然而，尽管已经建立了评估的方法和标准，例如临床研究或其他实证研究，在系统评价的背景下，对规范性文献（或规范性信息）的质量评估仍然是一个难题-不仅不清楚如何或应该做到，而且还不确定是否必须这样做。基于对“规范性文献”的务实定义以及对规范性文献/信息进行不同类型的系统评价的类型学，本文确定并批判性地讨论了进行质量评估的三种可能策略。结论本文将论证这三种策略都不能为与规范性文献/信息的质量评估相关的问题提供一个通用且令人满意的解决方案。仍然，