- Authors: Heather L Colquhoun, Tiago Silva Jesus, Kelly K O’Brien, Andrea C Tricco, Adora Chui, Wasifa Zarin, Erin Lillie, Sander L Hitzig, Samantha Seaton, Lisa Engel, Shlomit Rotenberg, Sharon E Straus
- Publication Year: 2021
- Journal: Archives of Physical Medicine and Rehabilitation, 102(2), pp 340-342
- Link: https://doi.org/10.1016/j.apmr.2020.10.121
LETTER TO THE EDITOR
Apropos «Scoping Review on Rehabilitation Scoping Reviews»
Dr Dijkers raised some important perspectives. Evaluating methodological quality of primary studies in scoping reviews is an ideal issue for further debate and additional guidance. Although the rationale for assessing methodological quality (ie, risk of bias) in systematic reviews of intervention effectiveness does not apply to scoping reviews, there may be logical reasons to evaluate and report on the quality of studies included in a scoping review. For example, when determining research gaps in the literature (a common objective of a scoping review), finding a large volume of research in one particular area would typically lead one to report that a gap (for that particular area) does not exist. However, if all of the literature is of poor quality, it would still be a gap, and important to know. Alternatively, if a scoping review aims to map how a complex topic has been approached or covered by the literature regarding research questions about how much, by whom, and with which publication or study type (including perspective and theoretical papers), it might not be relevant to conduct a quality appraisal. Methods need to address the research questions; in the case of scoping reviews, they are typically broader than in (for example) systematic reviews of intervention effects, for which risk of bias assessment is an imperative.
The point regarding method of syntheses (ie, qualitative or other) is well taken. Our aim had been to report how many studies used a qualitative analysis, not to report on how all studies summarized their data. That said, a better understanding of how syntheses is conducted in all scoping reviews is worthy of being addressed in additional research (eg, secondary analysis, a future update to the review).
The issue of the iterative nature of scoping reviews is another point worth discussion and we agree that more attention, debate, and reporting could be given to this topic. Systematic review experts might suggest that all types of reviews are iterative in nature. Unfortunately, the iterative nature of scoping reviews at times can be used as a license to make it up as you go along and this might have contributed to the perception of scoping reviews as a less than systematic approach. Although changes to a scoping review can be made (as long as they are carefully documented and include the effect on results), taking the notion of back and forth too far inevitably leads to problems with the integrity of the review (eg, changes in study selection halfway through screening, changes to the question that are not consistent with the search terms, etc).
Scoping reviews continue to be an emerging area of knowledge syntheses, although an increasing number of methods guidance exists1 including reporting guidance.2 We expect, and indeed look forward to, advances to the field.