Table 1 Defining programme theory

Programme theory: A programme theory is the overarching theory or model of how an intervention is expected to work. The ‘theory’ in a programme theory “can be an articulation of practice wisdom or of tacit assumptions – that is, not only a formal, research-based theory” ([11], p. 33). A programme theory is made up of two components, a theory of change and a theory of action.

Theory of change: A theory of change explains the causal processes or hypothesised mechanisms that lead from activities to outcomes [12].

Theory of action: A theory of action details what the programme or intervention will do in order to activate the change theory [11].

Logic model: A logic model is a graphical representation of a programme theory, which maps out the links between the intervention and anticipated outcomes.