Evaluation of the CompreHensive geriAtRician-led MEdication Review (CHARMER) Deprescribing Intervention in Hospital: Protocol for a Cluster Randomised Stepped-Wedge Trial

Background: Whilst almost half of older adults admitted to hospital are prescribed potentially inappropriate medicines, less than 1% have a medicine proactively deprescribed during admission in the UK. The CompreHensive geriAtRician-led MEdication Review (CHARMER) intervention, is designed to address geriatricians’ and pharmacists’ barriers and enablers to deprescribing. The CHARMER definitive trial will evaluate effectiveness, cost-effectiveness and safety. Methods and analysis: A stepped-wedge cluster randomised controlled trial will be conducted in 20 hospitals in England, with four hospitals in reserve. All hospitals will collect baseline data. Every three months, five hospitals will be randomised to receive the intervention. The intervention, implemented by a local project manager, comprises: A hospital action plan to set deprescribing as an organisational goal; workshops for pharmacists and geriatricians to change beliefs about deprescribing; weekly briefings between geriatricians and pharmacists to discuss opportunities for deprescribing; benchmarking reports to compare deprescribing performance across participating hospitals. With an average 200 patients admitted and discharged during each step, the study will have 89.5% power at 5% significance level and ICC of 0.05 to detect a 3% difference in 90-day re-admission rate from 16.7% versus 13.7%. Anonymised routinely collected data, including readmissions will be obtained for all patients admitted during the study period. Enhanced data collection periods of one month during control and intervention periods will be used to recruit patients and data for secondary outcomes and process evaluation. Ethics and dissemination: Ethical approval for the study was obtained from Wales REC2 on 04/07/2023, REF: 23/WA/0184. Confidential Advisory Group approval (REF: 23/CAG/0073) was obtained on 06/07/2023 to enable collection of anonymised routinely collected data for all participants during the non-enhanced data collection periods. The research team will follow the Guide to Disseminating Research (GuiDir) framework, which includes identification of target audiences for dissemination from the outset, agreeing dissemination goals, developing a dissemination plan, choosing appropriate dissemination channels and tracking the impact of the dissemination. Depending on the trial result the goal would ultimately be national implementation of intervention and consequently target audiences will include service commissioners and representative bodies for the different actors within the trial.