“…2 ). The number of studies assessing implementation outcome measures has increased over time, with one study published in 1998 [ 79 ], through to eight studies published in 2018/2019 [ 27 , 42 , 45 , 49 , 56 , 62 , 76 , 77 ]. Studies were predominantly conducted in high-income countries, with the majority conducted in the USA alone ( n = 22) [ 25 , 29 , 30 , 35 , 37 – 39 , 44 , 46 , 47 , 53 , 57 , 58 , 64 , 66 , 67 ].…”