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

Design: Pragmatic cluster randomised controlled trial of a complex intervention with nested mixed methods process and economic evaluations. Setting: UK general practices Literature review: A search of Medline with combinations of terms relating to primary care, risk registers and asthma revealed no relevant papers other than our studies (Smith 2012; Noble 2006); furthermore, there are no relevant studies registered in clinical trial databases. Target population: Patients at high risk of asthma exacerbations/death Inclusion/exclusion: 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=105370) 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: 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. Measurements: 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 measure of effectiveness will be based on the primary outcome measure. 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 (coefficient of variation 0.72), an intra-cluster correlation coefficient of 0.01 and to allow-for 10% drop-out, we will recruit 270 clusters, 10530 patients. 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.