Abstract
PURPOSE: Dekker et al. (2016) propose an updated definition of behavioural medicine. METHOD: In this commentary, we discuss how the field and the disciplines involved have changed over time before suggesting small amendments to the proposed definition. RESULTS: We suggest that the range of medicine which might be considered 'behavioural' is increasing to encompass virtually all medical practice. In addition, the role of behaviour and the potential for behaviour change as a means of improving health have become increasingly important. A defining characteristic of behavioural medicine is the involvement of multiple disciplines, working together or in parallel and, as the extent of the field expands, more disciplines are likely to be involved. CONCLUSION: We therefore propose that the definition should represent the full width of the research, practice and disciplines involved in behavioural medicine.