Designing and Conducting Motivational Interviewing Research in Veterinary Clinical Settings: A Practical Guide for Researchers.

Motivational interviewing (MI) is gaining traction in veterinary medicine as an evidence-based approach for engaging clients in conversations that strengthen their intrinsic motivation to change behaviours that affect the welfare of animals in their care. While MI has a substantial and well-established evidence base across human healthcare and related fields, the veterinary evidence base remains small and is currently limited by study design challenges, inconsistent fidelity measurement, and outcome measures that rarely extend beyond short-term changes in communication behaviour. Existing methodological guidance addresses treatment integrity and theoretical mechanisms but does not provide an integrated framework for designing robust studies across the range of questions relevant to veterinary practice. This paper addresses that gap by providing practical methodological guidance for researchers designing MI studies in veterinary clinical settings. A novel conceptual model of the MI implementation pathway, mapping the journey from practitioner awareness through training and delivery to client outcomes, is used to organise key research questions that need to be answered in veterinary contexts. Guidance is then provided on selecting appropriate study designs, measuring fidelity and outcomes, estimating sample size, and managing the practical and ethical challenges specific to veterinary clinical settings, alongside minimum reporting standards to support more rigorous and reproducible MI research.