Search strategy analysis
Table S8 outlines the results of four individual searches in EMBASE,
MEDLINE, CINAHL and COMET. Twelve studies (46%) were identified in all
four individual searches. Of the 16 studies with the primary aim of
developing COS, nine (56%) would have been identified in any single
search. One COS study was not identifies in any electronic database
search, but was identified in the COMET register.40Despite all 26 included studies being registered with COMET, four
studies were not identified in our search, due mainly to falling outside
our search parameters.