“…Of 19 systematic reviews analyzed, 10 included a mix of study designs (eg, randomized clinical trials [RCTs], observational cohort studies), 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 8 included only RCTs, 20 , 42 , 43 , 44 , 45 , 46 , 47 , 48 and 1 included only retrospective cohort studies. 49 …”