Applying behavioural science to increase uptake of the NHS Health Check: a randomised controlled trial of gain- and loss-framed messaging in the national patient information leaflet

The NHS Health Check (NHSHC) is a national programme for the prevention of non-communicable diseases. Patients aged 40–74 without an existing cardiovascular-related condition should be invited quinquennially. Uptake is lower than anticipated. We assessed the impact on uptake of two new behaviourally-enhanced leaflets (with the current national leaflet as a control), enclosed with the invitation letter: the first trial on the leaflet. A double-blind three-armed randomized controlled trial was conducted. The new leaflets were shorter (two pages, instead of four); one was loss-framed (‘don’t miss out’) and the other was gain-framed (‘make the most of life’). The participants were patients from 39 practices in Lewisham and 17 practices in NE Lincolnshire, who were allocated to interventions using a random-number generator and received one of the leaflets with their invitation letter from April–September 2018. The outcome measure was uptake of an NHSHC by November 2018. The trial was powered to detect a 2% effect. Uptake was 17.6% in the control condition (n = 3677), 17.4% in the loss-framed condition (n = 3664), and 18.2% in the gain-framed condition (n = 3697). Leaflet type was not a significant predictor of NHSHC uptake in a logistic regression that controlled for demographic variables, with GP practice as a random effect. Statistically significant predictors of uptake included location (higher uptake in Lewisham), age (increased age was associated with increased attendance) and sex (higher uptake in females). The Bayes Factor comparing the null to a hypothesis of differences between conditions was 416, which is extreme evidence in favour of the null hypothesis. There was no evidence for a meaningful effect of either a loss-framed or gain-framed behaviourally-informed leaflet type on uptake, which is surprising, given that behaviourally informed letters have improved uptake of NHSHCs. It is possible that people do not pay attention to leaflets that are enclosed with letters, or that the leaflet continues to support informed decision-making but this does not affect uptake. Clinicaltrials.gov, NCT03524131. Registered May 14, 2018. Retrospectively registered.