Trial Registration

The ARRISA-UK study is registered with Controlled Clinical Trials: ISRCTN95472706

The ARRISA-UK study is also registered on the UK Clinical Research Network: Study ID=18118.


The ARRISA-UK Trial is also supported by:

This website presents independent research commissioned by the National Institute for Health Research (NIHR). The views and opinions expressed by authors in this website are those of the authors and do not necessarily reflect those of the NHS, the NIHR, NETSCC, the Health Technology Assessment Programme or the Department of Health.


About the ARRISA-UK Study

About Us

  • The At-Risk Registers Integrated into primary care to Stop Asthma crises in the UK study (ARRISA-UK).
  • The study is funded by the National Institute for Health Research's Health Technology Assessment Programme.
  • It is a randomised cluster controlled trial of a brief training of GP practice staff and of the identification and flagging of records of high risk asthma patients to determine if this it may reduce the occurrence of severe asthma related events. In this study design it is the GP practice that is randomised.
  • There is a target for enrolment of 270 GP practices throughout England Scotland and Wales.
  • The study intervention is to provide online training for GPs, Nurses and reception staff in managing care for those asthma patients identified as being at the highest risk of having a severe event (hospitalisation or death); often this involves prioritising all patient interactions with practice staff to maximise the utility of care opportunities to assess and improve the patient's asthma status.
  • Practices will be assisted for automated identification of asthma patients identified as being at the highest risk of having a severe event using information routinely recorded locally in the GP practice database. This may then be assessed and modified by practice staff to adjust the identification based on their knowledge of their patients.
  • The study runs from December 2014 through October 2022, with practice recruitment and setup from mid 2015 through mid 2018, with 1 year of follow up of the intervention at the practices.
  • In addition to the use of anonymous routine data from the practices, some patients and staff from some of the practices will be invited to participate in interviews and focus groups to discuss the process of using the register and how it may affect asthma care at the surgery.

Further information

If you would like a more detailed background and explanation:

Scientific Abstract

At-Risk Registers Integrated into primary care to Stop Asthma crises in the UK  (ARRISA-UK)

A pragmatic cluster randomised trial with nested economic and process evaluations examining the effects of integrating at-risk asthma registers into primary care with internet-based training and support.


Pragmatic cluster randomised controlled trial of a complex intervention with nested mixed methods process and economic evaluations.


UK general practices

Target population

Patients at high risk of asthma exacerbations/death


270 primary care practices, excluding practices with existing formal, prospective processes for targeting patients with at - risk asthma. All the patients identified as having at - risk asthma according to a validated algorithm (n=10530) will be included, except those with recorded refusal for use of anonymous data in research.

Health technology 

At - risk registers will be created using automated electronic searches identifying at -risk criteria. Training will be delivered via web - based eLearning modules and “webinars” to representatives of all categories of practice staff to train them on how to respond to electronic alerts/flags to ensure best practice care. The flags will tag the electronic health records of at - risk patients to alert all staff at all patient - practice interactions. A practice based study lead will receive email reminders at 6 weeks and 6 months.


Control practices will continue routine care, including Quality and Outcome Framework driven practice- based annual asthma reviews and patients’ use of routine and emergency primary and secondary care services as required the but not the flagging or training.


The primary outcome is the difference in the proportion of at - risk patients with an asthma- related crisis event (A&E attendance, hospitalisation or death) over 12 months. Secondary outcomes: time to first crisis event, asthma control, prescribed medications, medication adherence, smoking status, all cause admission and death, health care costs in all and “at - risk” asthma patients.

Anonymous routinely- collected clinical data from patients will be captured. Health economic analysis will be from an NHS perspective, where the primary outcome will be the measure of effectiveness.

Routine data on processes of care, and questionnaires from practice staff completed before, during and after the training and after 12 months of the intervention, plus exit focus groups and interviews will contribute to the process evaluation.

Sample size

In order to have 90% power to detect a difference in primary outcome from 7% to 5% assuming an average cluster size of 39 (ICC 0.01) and allowing for 10% drop - out, we will recruit 270 clusters, 10530 patients.

Project timetable

Regulatory approvals ( - 6 to 0 months), production and evaluation of training programme in one region (0 to 6 months), recruitment of practices (2 to 12 months), training (9 to 24 months), follow up (21 to 36 months), focus groups (30 to 36 months), completion/cleaning dataset (37- 42mth), analysis & report (42 - 48mth).

Study funding 

Study funding is from the NHS’s National Institute of Health Research, Health Technology Assessment Programme, sponsored by the University of East Anglia (UEA) and based at the Norwich CTU at Norwich Medical School. Prof. Andrew Wilson, Clinical Professor/Consultant Physician of respiratory medicine at the UEA and Norfolk and Norwich University Hospitals NHS Foundation Trust is the Chief Investigator. He is working with a distinguished team of researchers from other universities, general practice, the charity Asthma UK, and other research organisations throughout the UK.

Expertise in team

Expertise in patient and public involvement (PPI), primary and secondary care physicians with research and clinical interest in at - risk asthma, health technology assessments, pragmatic cluster randomised controlled trials, statistics, health economics, qualitative research and comprehensive evaluation of complex intervention.

Study Summary

Unfortunately, far too many patients with asthma are admitted to hospital (approximately 72,000) or die (approximately 1150) unnecessarily in the UK every year. We have excellent drugs available for asthma and clear advice on prescribing them that should allow asthma to be controlled in most patients. It is known that certain asthma patients are at greater risk of being admitted or dying than others and that targeting intensive support and care to these patients improves their health. We have undertaken a study that identified ‘at-risk’ patients within GP practices and used computer-based systems to create pop-up alerts when these patients contact the practice. Practice staff were trained on what to do when they see the alert. This didn’t reduce the total number of attacks but reduced the hospital admissions as more patients appeared to receive appropriate treatment for their asthma. Based on these promising findings we wish to undertake a nationwide study to confirm that we can improve the care of these patients without costing the NHS too much or affecting the care of other asthma patients within GP practices.

We will identify 10530 patients who are at risk of having severe asthma attacks from 270 GP practices in six regions within the UK, by searching their practice records for factors that predict risk of attacks. In half of the GP practices, a pop-up alert will appear on the computerised medical notes whenever any of the ‘at-risk’ patients make contact with anyone in the practice. This alert will, for example, remind receptionists to book urgent appointments, GPs and nurses to advise patients to take their medication and follow their written asthma action plans (personalised documents which advise patients what to do when their asthma gets worse or better) and pharmacists to ensure patients take their medicines. All practice staff will receive training on how to respond to the alerts, supported by web-based resources and practice study champions, with reminders at 6 weeks and 6 months.

We will use data available routinely from the GP practice and will not need to collect information directly from patients for our study. After 12 months, we will count how many patients attended Accident and Emergency, had a hospital admission, or died due to asthma in each group. We will also find out how many people have well controlled asthma, what medications are prescribed for asthma, how often patients attend routine appointments and if they stop smoking. We will calculate how much this costs and whether it improves (or interferes with) the care of other patients with asthma in the practice. We will work out which patients gain the most from our study. With their permission, we will arrange focus groups and interview for patients and staff, to discuss their thoughts about the at-risk registers and the training and how it worked in practice.