Improvements in quality of clinical care in English general practice 1998-2003: longitudinal observational study

Abstract
Objective To measure changes in quality of care for three major chronic diseases (coronary heart disease, asthma, and type 2 diabetes) between 1998 and 2003. Design Longitudinal cohort study. Setting 42 general practices in six geographical areas of England (Avon, Bury/Rochdale, Enfield, Oldham, Somerset, South Essex). Participants Medical record data for 2300 patients with diabetes, asthma, or coronary heart disease in 1998, and 1495 patients in 2003. Main outcome measure Quality of care assessed against predefined evidence based review criteria. Results Between 1998 and 2003, quality of care improved markedly in terms of maximum possible scores on the review criteria, from 60.5% to 78.1% for coronary heart disease (change = 17.6, 95% confidence interval 13.9 to 21.4; P < 0.001), 60.1% to 70.3% for asthma (10.2, 4.6 to 15.8; P = 0.001), and 70.4% to 77.7% for diabetes (7.3, 3.5 to 11.1; P = 0.001). Important changes occurred to several indicators potentially related to improved health outcomes. These included improved control of serum cholesterol (to ≤ 5 mmol/l) from 17.6% to 61.4% in coronary heart disease and from 21.5% to 52% in diabetes and control of blood pressure to ≤150/90 in coronary heart disease from 47.3% to 72.2% and to ≤145/85 in diabetes from 21.8% to 35.8%. A small, non-significant improvement in glycaemic control occurred among diabetic patients (37.9% to 39.7% with HbA1c < 7.4%). Significant improvements also occurred in the recording of exercise capacity and diet and weight advice for patients with coronary heart disease; of smoking advice, peak flow, and symptoms for patients with asthma; and of creatinine, weight, and HbA1c for patients with diabetes. Over the five years, more improvement in coronary heart disease care occurred in large practices and practices in affluent areas. Conclusions Substantial improvements were seen in quality of care for the three conditions studied between 1998 and 2003, a time of systematic quality improvement initiatives in the NHS. The changes were most marked for coronary heart disease. English general practices could be expected to achieve high clinical quality scores in the initial year of a new contact, which provides financial incentives for high quality care from 2004.