Edinburgh Napier University

  First paragraph:The form of delivery (FoD) is a vital part of any behaviour change intervention and not merely a by-product of operationalising theory and behaviour change techniques (BCTs). Behaviour change interventions consist of three broad groups of interconnected components: (1) BCTs (i.e., the content of the intervention); (2) theory (i.e., the processes throughwhich the intervention is believed to influence behaviour); and (3) the FoD (i.e., the way in which the intervention is delivered). Behaviour change science has made significant progress in specifying BCTs (Abraham & Michie, 2008; Michie et al., 2013), and understanding the behaviour change processes (Hall & Fong, 2010; Rothman, Sheeran, & Wood, 2009; Strack & Deutsch, 2004; West, 2006), with healthy critical debates helping advance theoretical innovation and testing (Sniehotta, Presseau, & Araujo-Soares, 2013). Some BCTs and associated theories specify some FoD elements. For instance, financial incentives and learning theory make several predictions about scheduling (Johnston, 2016). However, the majority of FoD elements and features are insufficiently specified to allow full operationalization and replication of an intervention (see Adams, Giles, McColl, & Sniehotta, 2014 for the example of financial incentives).