Objective: To evaluate the feasibility and implementation needs of a cholesterol guideline by assessing the effectiveness of simple dissemination as well as extensive implementation of this guideline on actual performance of general practitioners (GPs).
Design: Randomized controlled trial.
Setting and subjects: Thirty-two Dutch GPs in 20 general practices, 3950 patient records.
Interventions: Guideline dissemination to all 32 GPs, and a 5-month programme for improvement in the intervention group. This programme was developed after barriers to working according to the guideline had been investigated, and consisted of group education, desktop supportive materials, feedback on performance, and face-to-face instruction on location.
Main outcome measures: The outcome parameters were defined as quality of selective case finding and quality of diagnostic procedures, and were measured by chart audit.
Results: The quality of selective case finding, especially the targeting of cholesterol testing to those with positive cardiovascular risk profiles, did not improve following intervention. Performance of the procedure necessary to diagnose hypercholesterolaemia even deteriorated. The quantity of cholesterol testing increased in both groups, but this was probably explained by the increased availability of desktop cholesterol analysers.
Conclusions: Neither simple dissemination nor an intensive programme for improvement had measurable impact on actual performance on working according to the cholesterol guideline. Both the validity and the opinion about feasibility of the guideline in daily practice deserve more attention during guideline development.