Introduction

Tensions exist between ensuring quality of prescribing within budgetary constraints and the emergence of new technologies. The issues of good prescribing and medicines management are developing rapidly as standard practice within primary care organisations, with ambitions for community pharmacy by 2004¹. There is evidence that prescribing influences are complex and that GPs are reluctant to fully implement evidence based medicine for a number of reasons².

Aim

The overall aim of the project is to investigate prescribing and formulary use patterns between two PCTs in order to optimise prescribing activities. This phase of the study explores the influences on prescribing.

Method

The study is longitudinal in design uses a variety of methods throughout; each informing the other (questionnaire, interview, quantitative and qualitative assessment of prescribing audits and activities, and ePACT). To assess the perceptions of prescribers in the two PCTs of what influences their prescribing, a questionnaire was designed. This was sent to all GPs (n=271) in two East London PCTs. The questionnaire comprised two sections; the factors perceived to influence prescribing and attitudes towards the local guidelines. Responses were recorded using either dichotomous or 5-step Likert scales. In this study, an initial hierarchical analysis was followed by a k-means cluster analysis.

Results

There was a 68% (n= 185) response to the questionnaire after follow-up. An initial hierarchical cluster analysis, using complete linkage, suggested three clusters to be used for a k-means analysis in order to identify homogenous groups of cases. Six items in the questionnaire proved most influential variables forming the clusters, with F-values ranging from 565.1 to 4.5 (p<0.05). These items generally related to the pharmaceutical advisor, drug representative influence and formulary usage. The cluster membership was evenly dispersed, comprising 49, 51 and 48 GPs respectively, with good euclidean separation. There were significant associations between GP characteristics and assigned cluster (for example gender; year of qualification; teaching practice; all at p<0.001). Cluster descriptions and separations were dependent on qualities of "good prescribing" and "poor prescribing".

Discussion

The findings show that GPs can be clustered according to their habits and attitudes to prescribing. The fact that GPs say they respond differently to different influences may help in shaping strategy in prescribing issues. Potentially GPs in different clusters should be targeted differently for optimisation of resource use. Further exploration of the identified clusters will be by qualitative follow-up with the prescribers themselves, those personnel involved in designing prescribing initiatives and those involved in higher levels of strategy.

References

1. Jackson C and Veitch B. Specialist faculties - the pragmatic rout to supporting professional competence. Pharmaceutical Journal 266:821-823, 2001

2. Freeman A C, Sweeney K. Why general practitioners do not implement evidence: qualitative study. BMJ 323:1-5 2001.