“…A majority of studies extracted were conducted in the USA [10][11][12][13][14][15], Canada [16][17][18][19][20][21], and Europe [22][23][24][25][26][27][28], with a few studies from New Zealand [29] and Asia [30][31][32][33]. One of the studies formed part of a multi-center coordinated project in 21 European countries [24], while 15 other studies were conducted in single sites [10-13, 15, 17, 18, 20, 21, 23, 25, 26, 28, 31, 32], and nine in multiple sites within the same country [14,16,19,22,24,27,29,30,33].…”