Childhood emotional maltreatment and trauma-related outcomes: a systematic review and multilevel meta-analysis.

People’s behaviour has an impact on their health and quality of life []. So, intervention efforts that stimulate and support behaviour change are warranted. Behaviour change is a means to an end. The assumption when developing a behaviour change intervention is that there is an established relationship between one or more behaviours and the health outcomes of interest (e.g. medical epidemiological data on the relationship between dietary behaviours and HbA1c). Acyclic Behaviour Change Diagrams (ABCDs) have been developed to foster transparent development, evaluation, and reporting of behaviour change interventions []. ABCDs are a visual representation of the assumptions regarding causal-structural chains that underlie the putative active ingredients of such interventions (). In other words, they represent the logic behind these interventions - from to intervene to is targeted and ? Causal-structural chains link the behaviour change principles that are applied in an intervention to the (determinants of) behaviour of interest in that intervention. The upper chain represents the generic logic of chains concerning behaviour change interventions, going from how (blue parts of the chain) to what (green parts) and why (purple parts). Interventions consist of multiple of these causal-structural chains. The second chain is one example in a behaviour change context. The lower chains are two simplified examples using medical analogies. These examples are meant to represent one specific chain relevant to these diseases (i.e. chlamydia and osteoarthritis) and not the complexity of the underlying medical model. Insight into this logic helps to get a better grasp of an intervention and makes it possible to discuss its underlying assumptions in a multidisciplinary development team. It is essential to have behaviour change expertise on board of such teams, yet this does not imply that each and every team member is familiar with behaviour change jargon and reasoning. Medical analogies are therefore helpful in facilitating communication in teams with doctors and other health professionals about the logic behind behaviour change interventions. This commentary serves to explain the logic of ABCDs and make it more accessible to multidisciplinary teams through these medical analogies. ABCDs focus on causal-structural chains and can be used within existing intervention development approaches (e.g. Intervention Mapping, Behaviour Change Wheel []).