Preferences for participating in a new community pharmacy alcohol brief intervention in Thailand: Discrete choice experiment with assessment of external validity
Purpose: To explore the clients’ preferences for brief alcohol intervention features delivered by community pharmacists, and to evaluate the external validity of discrete choice experiment (DCE) by comparing predicted choices with actual choices. Methods: A generic DCE questionnaire was filled out by 300 drinking clients selected by nine community pharmacists based on convenience sampling. Respondents made repeated choices between two hypothetical ABI alternatives according to five attributes, and a third alternative of no participation. One choice task was added to test choice rationality. Choice data were analyzed using a mixed logit model. The predicted choice external validity assessment of DCE was compared to actual participation at the population and individual levels. Results: A total of 162 customers from one pharmacy who passed the choice rationality test were included in the preference model. Most attributes in the model were significant at the 5 % level, influencing participation in the ABI service. The aggregate decision to participate in the ABI service was minimally overestimated by the DCE model. At the individual level, a lower accuracy was observed. Conclusion: The results provide useful information for policymakers to implement the alcohol-related problem prevention strategy in community pharmacies in Thailand. Future research may require an establishment of the DCE model's external validity to incorporate terms of interaction and assess why the participants did not do as they had decided