“…Third, in a UK context, there is a literature on HB, which has examined a number of issues including: the efficacy of the HB system as a whole (Kemp, 1998(Kemp, , 2000Kemp et al, 2002;King, 1999;Stephens, 2005); comparing systems (Kemp, 2000;Priemus & Kemp, 2004); the impact of changes to the system (Gibbons & Manning, 2006;Fenton, 2011); and its cost (Johnson, 2015;Phillips, 2013;Wilcox & Perry, 2014).…”