How do clinicians use guidelines in decision making?
This thesis presents a series of studies about general medical practitioners’ patient management decisions in depression and the role of the clinical guideline within these. The goal of the research was to identify the factors that influence their prescribing and to investigate how guideline use could be increased so as to promote clinical effectiveness. A lens model study found that GPs tend to over prescribe compared with the guidelines and place much more emphasis on patients’ reports of thoughts of suicide and sleep disturbance than the guideline. Although GPs’ judgement data were well described by regression models, a simple fast and frugal model of decision-making explained the judgement data equally well. A cluster analysis was carried out on the resulting GPs’ decision policies and 3 clusters emerged which could be differentiated by the size of practice they worked in. GPs in the larger practices had decision policies, which were more like those of guideline recommendations. GPs were found to have good self-insight in to their decision-making when a policy recognition task was used. A further analysis found that GPs in one area in England prescribed at a greater rate than those in the Grampian region of Scotland and decision policies showed that patient treatment preference had less influence on the English GPs’ decisions. The results from these quantitative studies were explored further by using in-depth interviews with GPs. A number of factors which help to explain why the GPs are sometimes prevented from following guideline recommendations and fulfilling patient treatment wishes and why changing behaviour in order for it to be more compliant with guideline recommendations it so difficult.