The determinants of antimicrobial prescribing among hospital doctors in England: a framework to inform tailored stewardship interventions

Little is known about the determinants of antimicrobial prescribing behaviour (APB), how they vary between hospital prescribers or the mechanism by which interventions are effective. Yet, interventions based on a sound theoretical understanding of APB are more likely to be successful in changing outcomes. This study sought to quantify the potential determinants of APB among hospital doctors in south-west England.

This multicentre, quantitative study employed a closed answer questionnaire to garner hospital doctors' views on factors influencing their APB. Underlying constructs within the data were identified using exploratory factor analysis and subsequent pairwise comparisons assessed for variance between groups of prescribers.

The questionnaire was completed by 301 doctors across four centres (response rate ≥ 74%) and three key factors were identified: autonomy, guidelines adherence and antibiotic awareness. The internal consistency for the questionnaire scale and for each factor subscale was good (α ≥ 0.7). Subgroup analysis identified significant differences between groups of prescribers: autonomy scores increased with grade until at the specialist trainee level (P ≤ 0.009), foundation doctors scored higher for guidelines adherence than consultants (P = 0.004) and specialist trainees (P = 0.003) and United Kingdom trained doctors scored higher than those trained abroad for antibiotic awareness (P < 0.0005). Scores did not vary significantly between doctors from different centres.

Autonomy, guidelines adherence and antibiotic awareness were identified as important factors relevant to APB, which vary with experience and training. A theoretical framework is offered to facilitate development of more effective, tailored interventions to change APBs.