“…The 25 selected studies were published between 2009 and 2017. Fourteen studies were European ( 9 , 10 , 11 , 12 , 13 , 14 , 15 ) (seven from Norway ( 16 , 17 , 18 , 19 , 20 , 21 , 22 )), five from Japan ( 23 , 24 , 25 , 26 , 27 ), five from USA ( 28 , 29 , 30 , 31 , 32 ) and one from India ( 33 ). We considered the findings in three groups: (1) scans performed by experienced users ( n = 16); (2) scans performed by non-expert physicians, with little or no prior experience ( n = 7); (3) scans performed by nurses with variable experience ( n = 2).…”