Background

The theory of planned behaviour (TPB) has been used successfully to develop interventions to promote individual health behaviours. However, little is known about whether interventions based on TPB can effectively improve the practice of health professionals. The aim of this study was to gain further insight into the potential utility of TPB in this area by conducting a process study alongside an ongoing trial of an intervention to change professional practice. The cluster-randomised trial evaluated two educational interventions (educational outreach visits and continuing education sessions) as a means to increase appropriate sales and decreasing inappropriate sales of anti-fungal agents by community pharmacists to women presenting with symptoms of vaginal candidiasis. Neither of these interventions was associated with a change in practice.

Methods

Questionnaires assessing intentions, perceived behavioural control, attitude, subjective norm, salient beliefs and past behaviour were developed using standard methods. They were distributed by post to all 120 eligible pharmacies in the Grampian region of Scotland in March 2000, prior to recruitment into the trial. In January 2001 (post intervention), the same questionnaire was distributed to the 60 pharmacies that participated in the trial.

Results

Completed questionnaires were returned from 76 pharmacies at Time 1 (63%), and 50 at Time 2 (83%). Scores on the intention measure showed a strong negative skew at baseline, suggesting that pharmacists were already highly motivated to sell anti-fungal agents. There were no significant differences between intervention and control groups on measures of intention (F = 1.56, df=4, p=0.21) or any other TPB components at Time 2.

Conclusion

These findings suggest that the educational interventions were unsuccessful because pharmacists were already motivated to sell anti-fungal agents. Further efforts in this area may be best directed towards post-intentional factors. The TPB has provided useful process information in this study, suggesting that intervention studies using this model to improve professional practice are warranted.