“…12,16, All e-mails were sent within a period of 24 h. The authors of six (18%) studies replied. [29][30][31]33,38,52 Five RCTs, [42][43][44][45]51 13 CCTs, 12,25,28,29,32,[35][36][37]40,41,46,47,49 and 18 retrospective studies 16,[20][21][22][23][24]26,27,30,31,33,34,38,39,48,50,52,53 were included in the meta-analysis.…”