Background: The Behaviour Change Technique Taxonomy v1
(BCTTv1) specifies the potentially active content of behaviour change
interventions. Evaluation of BCTTv1 showed the need to extend it into
a formal ontology, improve its labels and definitions, add BCTs and
subdivide existing BCTs. We aimed to develop a Behaviour Change
Technique Ontology (BCTO) that would meet these needs.
Methods: The BCTO was developed by: (1) collating and synthesising
feedback from multiple sources; (2) extracting information from
published studies and classification systems; (3) multiple iterations of
reviewing and refining entities, and their labels, definitions and
relationships; (4) refining the ontology via expert stakeholder review
of its comprehensiveness and clarity; (5) testing whether researchers
could reliably apply the ontology to identify BCTs in intervention
reports; and (6) making it available online and creating a machinereadable
version.
Results: Initially there were 282 proposed changes to BCTTv1.
Following first-round review, 19 BCTs were split into two or more
BCTs, 27 new BCTs were added and 26 BCTs were moved into a
different group, giving 161 BCTs hierarchically organised into 12
logically defined higher-level groups in up to five hierarchical levels.
Following expert stakeholder review, the refined ontology had 247 BCTs hierarchically organised into 20 higher-level groups.
Independent annotations of intervention evaluation reports by
researchers familiar and unfamiliar with the ontology resulted in good
levels of inter-rater reliability (0.82 and 0.79, respectively). Following
revision informed by this exercise, 34 BCTs were added, resulting in a
final version of the BCTO containing 281 BCTs organised into 20
higher-level groups over five hierarchical levels.
Discussion: The BCT Ontology provides a standard terminology and
comprehensive classification system for the content of behaviour
change interventions that can be reliably used to describe
interventions