Table 2

Quality assessment of included reviews using the AMSTAR tool

QuestionWeed et al14McCartney et al6
1.Was an ‘a priori’ design provided?YY
2.Was there duplicate study selection and data extraction?YY
3.Was a comprehensive literature search performed?YY
4.Was the status of publication (ie, grey literature) used as an inclusion criterion?YY
5.Was a list of studies (included and excluded) provided?N-only included studiesN-only included studies
6.Were the characteristics of the included studies provided?YY
7.Was the scientific quality of the included studies assessed and documented?YY
8.Was the scientific quality of the included studies used appropriately in formulating conclusions?YY
9.Were the methods used to combine the findings of studies appropriate?YY
10.Was the likelihood of publication bias assessedYN/A—authors state this not possible
11.Was the conflict of interest stated?U (although commissioned by Department of HealthY
  • N, no; N/A, not applicable; U, unclear; Y, yes.