Intervention components and behaviour change techniques (BCTs)
Behaviour change interventions should target and address the barriers
and enablers (determinants) to the target behaviour. There are multiple
determinants of behaviour and thus interventions require several
components to address them. Behaviour change interventions are therefore
complex interventions comprising of multiple interacting components (5).
Behaviour change techniques (BCTs) are the irreducible ‘active
ingredients’ of a behaviour change intervention that bring about
behaviour change
Selection and formulation of BCTs into tangible components that can be
combined to form an intervention should be informed by evidence and
behaviour change theory. Evidence provides a rich understanding of the
behavioural determinants. Theory enables the behavioural mechanisms by
which BCTs exert their effects to be defined. There are numerous
behaviour change theories, many with overlapping constructs thus
selecting any one theory to fully represent the potential determinants
of a behaviour is challenging. The theoretical domains framework (TDF)
is an integrative framework of behaviour change theories comprising 14
mechanisms of action domains such as knowledge , beliefs
about capabilities and emotion (6) and has been successfully
applied to define the behavioural mechanisms of action of deprescribing
in hospital (7).
Interventions and how they are hypothesised to change behaviour and
resultant outcomes can be visually depicted in a logic model. Logic
models represent the causal theoretical assumptions of an intervention
and moderating factors. They can also describe the context within which
an intervention is implemented and how the two interact. Below we
outline some of the key components of a logic model that should be
tested and refined using learning from feasibility testing and
evaluation processes.