In defence of the bioethics scoping review: Largely systematic literature reviewing with broad utility.

There is growing interest in the possible role of systematic methods of reviewing literature in bioethics. This has arisen alongside the growth of empirical bioethics and a general push towards introducing some level of rigour and reproducibility into scholarship in the field. However, there remain a range of approaches to reviewing literature utilized in bioethics, which vary significantly in their 'systematicness' and suitability for different purposes. In this article, we first detail a taxonomy of various existing reviews used in bioethics and how scholars have defended and critiqued them, presenting them relationally along axes of 'systematic' and 'critical'. Considering the suitability of these reviews, we then explore the inherent differences between normative and empirical literature in relation to how they can be reviewed. In particular, we highlight the challenges in reviewing both normative and empirical literature in a single review. As something of an answer to these challenges, we introduce and defend the scoping review as, in many ways, a method of reviewing literature with wide-ranging utility in bioethics. Demonstrating the many benefits of the scoping review, we then position it within the existing taxonomy of reviews, ultimately arguing that its combination of systematic and critical, inclusive of a reasonable degree of flexibility, makes it deserving of increased attention and use in bioethics.