Skip to content
View commentaries on this research

This is a plain English summary of an original research article

In adults with poorly controlled diabetes, text messages offering advice and support can improve self-management and blood sugar control.

This trial included 366 adults with type 1 or type 2 diabetes in New Zealand. An automated system delivered individually tailored text messages to participants over a nine-month period to support self-management of blood sugar. The control group received usual care, comparable to that in the UK.

The text message group had a small reduction in blood sugar levels. Although the levels remained above target levels in both groups, the reduction is still likely to help reduce complications. The text message service was well-received by participants with almost all willing to recommend the intervention to others. However, the costs of the intervention were not reported.

Why was this study needed?

There are 3.8 million people in the UK with diabetes. About 90% of these have type 2 diabetes. It is estimated that the cost of diabetes and its complications to the NHS is £9.8 billion per year. Good blood glucose control can help prevent complications and is central to the management of diabetes. This is measured by a blood test called HbA1c which indicates the average blood glucose over the previous two or three months. For people with diabetes, the target HbA1c is usually below 48mmol/mol.

There is growing interest in the use of tools such as mobile phones in the self-management of diabetes to prevent complications. This randomised controlled trial examined the effectiveness of a text message-based intervention designed to support people in self-management of their diabetes.

What did this study do?

The SMS4BG (self-management support for blood glucose) trial randomised 366 adults with poorly controlled type 1 or type 2 diabetes (HbA1c 65mmol/mol or more) to receive either text messages in addition to usual care or usual care alone. The texts were individually tailored to motivate participants to engage in behaviours relating to diabetes management.

The text messages were sent from an automated management system. The participants could choose the frequency and content of the messages. The system also enabled them to submit their blood glucose readings and monitor these over time through graphs.

This trial included a high proportion of ethnic minorities and took place in New Zealand, which may limit applicability to the UK. One funder of this study was involved in the development of the texting service which may introduce bias in favour of the intervention.

What did it find?

At nine months, compared with baseline:

  • HbA1c had reduced by more in the group receiving text message support than in the control group (adjusted mean difference −4.2mmol/mol, 95% confidence interval −7.3 to −1.2).
  • The average HbA1c levels in both groups remained higher than the target. The intervention group HbA1c reduced from 86 to 78mmol/mol. The control group HbA1c reduced from 83 to 79mmol/mol.
  • A decrease in HbA1c was observed in 75% of intervention participants compared with 59% of control participants.
  • Of 21 secondary outcomes that were assessed, improvements were seen in four: frequency of foot care, perceived overall diabetes support, self-reported health status, and how often people perceive they have symptoms related to diabetes.
  • Participants reported high levels of satisfaction with the text messaging program with 95% identifying it as being useful and 97% willing to recommend it to others.

What does current guidance say on this issue?

NICE guidelines for management of type 1 and type 2 diabetes recommend the monitoring of HbA1c at three to six-month intervals. Adults with either type of diabetes are usually advised to aim for a target HbA1c of 48mmol/mol (6.5%) or lower. Adults with type 2 diabetes on medication that can cause low blood sugar (hypoglycaemia) should aim for 53mmol/mol.

Structured education programmes are recommended in both type 1 and 2 diabetes focusing on diet, lifestyle, and adherence to drug treatment. However, the guidelines do not specify how the education is best delivered or the role of mobile technology.

What are the implications?

Text message support appears to be a safe, well received, and modestly effective adjunct to standard care for patients with poorly controlled diabetes. However, the HbA1c 4.2mmol/mol difference between the groups was small and did not reach the pre-set 5.5mmol/mol clinically meaningful difference by the researchers. Nevertheless, any improvement is likely to help reduce the risk of complications.

There is increasing interest and investment in UK programmes applying mobile technology to the prevention and management of diabetes and other chronic diseases.

Uncertainties remain around the long-term benefits of such interventions, their cost-effectiveness, their use in overcoming health care inequalities, and the optimal content and frequency of their messages.

Citation and Funding

Dobson R, Whittaker R, Jiang Y, et al. Effectiveness of text message based, diabetes self-management support programme (SMS4BG): two arm, parallel randomised controlled trial. BMJ. 2018;361:k1959.

Development of the SMS4BG was funded by Waitemata District Health Board. The trial was funded by the Health Research Council of New Zealand in partnership with the Waitemata District Health Board and Auckland District Health Board. This was associated with the Research Partnerships for New Zealand Health Delivery initiative.  Funding was also provided by the New Zealand Ministry of Health. The funding agencies were not involved with the analysis of study results or in the writing of the manuscript.



Diabetes UK. The cost of diabetes. London: Diabetes UK; 2014.

NHS website. Diabetes. London: Department of Health and Social Care; reviewed 2016.

NICE. Type 2 diabetes in adults: management. NG28. London: National Institute for Health and Care Excellence; 2016.

NICE. Type 1 diabetes in adults: diagnosis and management. NG17. London: National Institute for Health and Care Excellence; 2015.

Produced by the University of Southampton and Bazian on behalf of NIHR through the NIHR Dissemination Centre


  • Share via:
  • Print article
Back to top