BACKGROUND Screening cardiovascular disease (CVD) risk is an important part of CVD prevention. The success of screening is dependent on the rigour with which treatments are subsequently prescribed. AIM To establish the extent to which treatment conforms to guidelines. DESIGN AND SETTING Cross-sectional study of anonymised patient records from 19 general practices in the UK. METHOD Data relating to patient characteristics, including CVD risk factors, risk score and prescribed medication were extracted. CVD risk (thus eligibility for cholesterol and blood pressure-lowering treatment) was calculated using the Framingham equation. Guideline adherence was defined with descriptive statistics and comparisons by age, sex and disease were made using χ(2) tests. RESULTS Of the 34 975 patients (aged 40-74 years) included in this study, 2550 (7%) patients had existing CVD and 12 349 (35%) had a calculable CVD risk or were on treatment. CVD risk was formally assessed in 8390 (24%) patients. Approximately 7929 (64%) patients eligible for primary prevention therapy were being treated appropriately for their CVD risk. Guideline adherence was higher in younger patients (6284 [69%] aged 40-64 years versus 1645 [50%] aged 65-74 years, P<0.001) and in females (4334 [69%] females versus 3595 [59%] males, P<0.001). There was no difference in guideline adherence between patients where CVD risk had been recorded and those where CVD was calculable. Guideline adherence in patients with existing CVD was highest in patients with ischaemic heart disease (866 [ischaemic heart disease], 52%, versus 288 [stroke], 46%, versus 276 [other CVD], 39%; P<0.001). CONCLUSION There is scope for improvement in assessment and treatment for prevention of CVD in clinical practice. Increasing the uptake of evidence-based treatments would improve the cost-effectiveness of CVD risk screening programmes.