Impact of the GP contract on inequalities associated with influenza immunisation: a retrospective population-database analysis

Abstract
Influenza immunisation is recommended for all people aged ≥65 years and younger people with particular chronic diseases. The Quality and Outcomes Framework (QOF) has provided new financial incentives for influenza immunisation since 2004. To determine the impact of the 2004 UK General Medical Services contract on the overall uptake of, and socioeconomic inequalities associated with, influenza immunisation. Retrospective general-practice population database analysis in 15 general practices in Scotland, UK. Changes in influenza-immunisation uptake for those in at-risk groups between 2003-2004 and 2006-2007 were measured, and variation in uptake examined using multilevel modelling. Uptake rose from 67.9% in 2003-2004 to 71.4% in 2006-2007. The largest increases were seen in those aged <65 years with chronic disease, with uptake rising from 49.6% to 58.4%, but rates remained considerably lower than in those aged ≥65 years. Differences between practices narrowed (median odds ratio [OR] for two patients randomly selected from different practices: 2.13 (95% confidence interval [CI] = 2.00 to 2.26) in 2003-2004 versus 1.44 (95% CI = 1.40 to 1.49) in 2006-2007. However, inequalities in uptake by patient socioeconomic status did not change: adjusted OR for most deprived versus most affluent was 0.75 (95% CI = 0.70 to 0.80) in 2003-2004 versus 0.72 (95% CI = 0.68 to 0.76) in 2006-2007. Overall uptake rose significantly and differences between practices narrowed considerably. However, socioeconomic and age inequalities in influenza immunisation persisted in the first 3 years of the QOF. This contrasts with other ecological analyses, which have concluded that the QOF has reduced inequalities. The impact of financial incentives on inequalities is likely to vary, and some kinds of care may require more targeted improvement activity and support.