The effects of structure, process and outcome incentives on primary care referrals to a national prevention programme

Despite widespread use, evidence is sparse on whether financial incentives in healthcare should be linked to structure, process or outcome. We examine the impact of different incentive types on the quantity and effectiveness of referrals made by general practices to a new national prevention programme in England. We measured effectiveness by the number of referrals resulting in programme attendance. We surveyed local commissioners about their use of financial incentives and linked this information to numbers of programme referrals and attendances from 5170 general practices between April 2016 and March 2018. We used multivariate probit regressions to identify commissioner characteristics associated with the use of different incentive types and negative binomial regressions to estimate their effect on practice rates of referral and attendance. Financial incentives were offered by commissioners in the majority of areas (89%), with 38% using structure incentives, 69% using process incentives and 22% using outcome incentives. Compared to practices without financial incentives, neither structure nor process incentives were associated with statistically significant increases in referrals or attendances, but outcome incentives were associated with 84% more referrals and 93% more attendances. Outcome incentives were the only form of pay-for-performance to stimulate more participation in this national disease prevention programme.