Int J Qual Health Care (2018), 1–18, doi.org/10.1093/intqhc/mzy080

The version of this article originally published online included an erroneous reference to a PROSPERO registration number. There was also some information missing from Figure 1. The online version has been updated to correct these errors, for which the authors apologize.

This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (http://creativecommons.org/licenses/by/4.0/)