UCL Psychology and Language Sciences


Developing an ontology of MoA in behaviour change interventions and investigating its applicability

Developing an ontology of mechanisms of action in behaviour change interventions and investigating its applicability


Professor Susan Michie
Dr Alison Wright
Dr Fabianna Lorencatto

UCL team members

Professor Robert West
Candice Moore
Emily Haynes

Project start and end datesJanuary 2018-September 2021
FunderWellcome Trust - Collaborative Award in Science
University College London

Project Aims

This PhD project has three overarching aims:
(1) to explore the guidance needed on selecting specific mechanisms of action as targets in behaviour change interventions,
(2) to develop an ‘ontology’ of Mechanisms of Action within behaviour change interventions, and
(3) to investigate this ontology’s applicability.

Project details

This research is in collaboration with the Human Behaviour-Change Project (HBCP) which is developing the Behaviour Change Intervention Ontology (BCIO). To address ‘why’ behaviour change interventions change or fail to change behaviour, this PhD project focuses on developing an ‘ontology’ of mechanisms of action as part of the BCIO.

While there is a general consensus about the importance of theory in developing and evaluating behaviour change interventions, theories are often incomplete, overlap or propose different definitions for the same terms or vice versa the same definitions for different terms. By synthesizing mechanisms of action from theories and proposing disambiguated labels and definitions, an ‘ontology’ of mechanisms of action can help streamline the accumulation of evidence about mechanisms from published intervention reports.

Drawing on 83 theories of behaviour and behaviour change with 1733 constructs, the current project identified 1059 mechanisms of action. To form a preliminary Mechanism of Action Ontology, the identified mechanisms of action were hierarchically structured, and their labels and definitions were refined according to ontological principles.


Next steps

The preliminary ‘ontology’ of mechanisms of action will be refined by applying it to code mechanisms of action in published intervention reports and by seeking feedback from external behavioural science experts.