“…Of the 15 studies involving 6511 participants, seven were conducted in the United States, 10,11,[20][21][22][23][24] three in the United Kingdom, [25][26][27] three in mainland Europe, [28][29][30] one in Canada 31 and one in Australia. 32 Eight used a single-group pre-test/post-test design, 10,11,21,22,27,28,30,32 and four used a single-group post-test design. 23,24,29,31 Two studies used an RCT design, 20,25 and one used a non-random case-control design.…”