“…All the studies were implemented in Europe and North America (ten of them in the United States and Canada). Of the 16 studies identified, eight had a randomized clinical trial design [ 19 , 20 , 21 , 23 , 24 , 25 , 26 , 27 ], six were observational studies [ 28 , 29 , 30 , 31 , 32 , 33 ] and two were economic evaluations [ 22 , 34 ]. Of the clinical trials, five reports [ 20 , 24 , 25 , 26 , 27 ] were randomized controlled trials with a high-quality design, whereas two [ 19 , 23 ] were research letters that communicated brief reports of data.…”