Performance data was analysed from 7,637 practices across England during the first three years of the quality framework.
The study, conducted by researchers from the National Primary Care Research and Development Centre in Manchester, looked at 48 clinical indicators covering the care of conditions such as heart disease, diabetes, epilepsy and asthma.
Each practice was awarded points on a sliding scale based on the proportion of patients achieving targets.
In year one, the most deprived areas hit the targets 82.8 per cent of the time, compared with 86.8 per cent for the most affluent areas.
But by year three, the gap had narrowed with the poorest areas scoring 90.8 per cent compared with 91.2 per cent for the most affluent areas.
The Lancet Online 2008
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