Sending text messages reminding people to book their NHS health check following their invitation letter increases attendance. There is little evidence to support pre-notification text messages telling people an invitation would soon be sent.
NHS health checks are offered to adults aged 40 to 74 years. Identification and management of cardiovascular risk factors has been shown to save lives. Yet only half of adults attend a check when it is offered. This trial conducted across general practices in South London assessed the effect of sending pre- and post-invitation text messages, along with different forms of invitation letter. Brief time-limited letters, telling people their check was due next month, for example, seemed most effective. However, any form of letter combined with a reminder text was more effective than no reminder.
It’s also notable that attendance in this locality was 30% at best, far below the 75% target. So texting may have variable effects depending on local circumstances too.
Why was this study needed?
In 2016-17, heart disease and stroke accounted for a quarter of all deaths in England. They cost the NHS £7.4 billion per year and the wider economy £15.8 billion.
NHS health checks are designed to spot early signs of stroke, kidney disease, heart disease, type 2 diabetes or dementia, by checking weight, height, blood pressure, blood cholesterol and blood sugar, and assessing risk factors like smoking, alcohol, diet, physical activity or family history. Health checks take about 20-30 minutes and are estimated to save 250 to 500 lives annually in England. However, of 11.4 million people invited for health checks in 2013-18, only 48.9% attended.
Failure to remember receiving invitation letters is often reported as a reason for this. Invitation content has also been cited as important, with some evidence that people are more likely to attend if given pre-booked appointments. This trial aimed to look at the effect of both text message reminders and letter content on attendance at health checks.
What did this study do?
This randomised controlled trial took place in 28 general practices in Southwark, London (of 45 invited to participate). It included 13,809 patients aged 40 to 74 years who were eligible for an NHS health check between November 2013 and December 2014.
This trial assessed different combinations of interventions. Patients were first assigned to receive either a pre-notification text or not. They were then assigned to receive one of 4 types of invitation letter:
- standard control letter, detailing the health check in several paragraphs
- open-ended letter, briefly saying their check was due and asking them to call and book
- time-limited letter, as open-ended letter but asking them to attend in a limited time period, such as ‘your check is due in March’
- social-norm letter, as open-ended letter but adding testimonials from patients saying how the health check helped them.
Finally, they were assigned to receive a reminder text or not.
What did it find?
- Amongst invited patients, 24% attended health checks. This ranged from 18% of those sent the standard control letter with neither text pre-notification nor reminder, to 30% of those sent the time-limited letter with both text pre-notification and reminder. Comparatively, this latter group had almost doubled odds of attending (odds ratio [OR] 1.93, 95% confidence interval [CI] 1.52 to 2.44).
- All other approaches significantly increased the likelihood of attending compared with the standard letter and no texts, except the control letter with only the pre-notification text, and the time-limited or social-norms letters without text messages. These three approaches showed only 20-21% uptake.
- When accounting for sex, ethnicity, deprivation and practice variations, the time-limited letter with both texts remained most effective compared with the control letter and no text (adjusted OR 1.86, 95% CI 1.40 to 2.38). The open-ended and time-limited letters with reminder text were next most effective (respectively, OR 1.68, 95% CI 1.31 to 2.17; and OR 1.61, 95% CI 1.25 to 2.07). In the adjusted model, any letter content on its own without a text and the control letter with a pre-notification text were ineffective compared with the control letter alone.
- The reminder text appeared to be the most effective addition. For all three intervention letters (open-ended, time-limited and social-norm) fewer people attended a health check when a reminder text was not sent. Although the time-limited letter with both texts was most effective, there was not enough evidence to support the value of the pre-notification text.
What does current guidance say on this issue?
Public Health England (PHE) guidance on NHS health checks (2017) recommends that eligible adults should receive an invitation. To reduce inequalities PHE supports prioritising invitations to people at highest risk, for example, those in the most deprived areas.
PHE provides a template letter on the NHS health check website, which takes the form of a brief time-limited letter. They also recommend patient leaflets accompany the letter, outlining what patients can expect at the appointment. These are also available from the website.
The website includes detailed advice about behaviour changes that can reduce cardiovascular risk, and shares results of local and national programme evaluations.
What are the implications?
A previous Signal reported a similar London-based trial which found that sending behavioural questionnaires prior to invitation letters made no difference to health check uptake. This trial suggests that sending text messages reminding people to book can make a difference.
About 1,500 people were excluded from this trial because they didn’t have a mobile number. It is recognised that people who could most benefit from digital services, such as text messaging reminders or web-based appointments, are the least likely to be online or have a mobile phone. NHS Digital report that eleven million people (20% of the population of the UK) lack basic digital skills, or do not use digital technology at all. These are likely to be older, less educated and in poorer health than the rest of the population.
Local health and care services are advised by NHS Digital to take into account the needs of people who may be digitally excluded. This local study may help services better understand their populations and given that in 2017 over 90% of people owned a mobile phone, text messaging may be a useful way to improve the current low uptake of checks.
Citation and Funding
Sallis A, Sherlock J, Bonus A et al. Pre-notification and reminder SMS text messages with behaviourally informed invitation letters to improve uptake of NHS Health Checks: a factorial randomised controlled trial. BMC Public Health. 2019; 19(1):1162.
Funding was provided by the Department of Health and Social Care.
NHS Digital. Digital inclusion guide for health and social care. London: Department of Health and Social Care; 2019.
NHS website. England NHS health check factsheet. London: Department of Health and Social Care; 2019.
NHS website. NHS health check. London: Department of Health and Social Care; 2019.
NHS website. NHS health check best practice guidance. London: Department of Health and Social Care; 2017.
NHS website. Public Health England cardiovascular disease prevention initiatives, 2018 to 2019. Leeds: NHS Digital; 2018.
Statista. Mobile phone usage in the United Kingdom (UK) 2005-2017. London: Statista, Ltd.; 2018.
Produced by the University of Southampton and Bazian on behalf of NIHR through the NIHR Dissemination Centre