A ‘Reference ID’ should be created for each included
review, and used throughout the Overview. This would usually comprise
the last name of the first author and the year of the most recent citation
version for the review (e.g. Efron 2006). Where two or more reviews share
the same first author and year, a letter may be added (e.g. Efron 2007a,
Efron 2007b). Reviews are organized under two fixed headings as follows.
Reviews that specifically meet the eligibility criteria and are included in the overview.
Reviews (if any) that do not specifically meet the eligibility criteria and are not included in the overview.