Authors' objectives: Polypharmacy is a major challenge for patient safety and effective resource use. High-quality evidence supporting polypharmacy management is lacking.

Authors' results and conclusions: Phase 1: Intervention component design was informed by findings related to elements of the medication review, informatics and clinician training. Phase 2: Core intervention elements were successfully implemented in the pilot, although clinical delivery was hampered by disruptions due to the coronavirus disease pandemic. Phase 3: Participants were recruited between January and June 2022 (intervention N = 891, usual care N = 836), median age 73 years, 49% female, with median four long-term conditions and eight medications. No improvement in the primary outcome was observed (mean difference potentially inappropriate prescribing count − 0.007; 95% confidence interval −0.21 to 0.199). Treatment burden was slightly improved, and subgroup analysis suggested potential improvements in less complex patients. The process evaluation found general practitioners and pharmacists valued and benefitted from the model of interprofessional collaboration, which strengthened working relationships and provided an opportunity for knowledge sharing and joint decision-making that supported management of clinical uncertainty. Most patients (73.2%) reported satisfaction with the review, with satisfaction strongly associated with perceptions of shared decision-making. There was no evidence of cost-effectiveness, although the economic evaluation did not quantify the aforementioned benefits or other broader factors of potential interest to decision-makers.

Authors' methods: Phase 1: Qualitative interviews and focus groups with patients and professionals explored views/experiences of existing National Health Service Scotland interventions, informing development of core intervention components. Phase 2: An external pilot-feasibility study was conducted in five general practitioner practices to optimise the Improving Medicines use in People with Polypharmacy in Primary care intervention. A formative mixed-methods process evaluation examined intervention implementation, alongside evaluating trial processes and collecting data to inform phase 3. Phase 3: A pragmatic, open-label two-arm parallel cluster-randomised trial was conducted in English general practice. The intervention (19 practices) comprised a structured, collaborative and patient-centred approach to medication review, supported by informatics, clinician training, performance feedback and financial incentivisation. The comparator was usual care (18 practices). Up to 50 adults receiving ≥ 5 regular medications, with ≥ 1 indicator of potentially inappropriate prescribing, were reviewed per practice over 6 months. Primary outcome was number of potentially inappropriate prescribing indicators at 26-week follow-up. Secondary outcomes included patient-reported measures and service use. Cost-effectiveness and cost–utility analyses were conducted (primary economic outcome quality-adjusted life-years). A mixed-methods process evaluation (patient surveys, patient/clinician interviews, audio-recorded observations) explored implementation. Key limitations include concurrent changes in usual care, potentially insensitive outcome measures and limited study-population generalisability.

Project Status: Completed

URL for project: https://www.journalslibrary.nihr.ac.uk/programmes/hsdr/NIHR136218

Year Published: 2026

URL for published report: https://www.journalslibrary.nihr.ac.uk/hsdr/GJRP0919

URL for additional information: English

English language abstract: An English language summary is available

Publication Type: Full HTA

Country: England, United Kingdom

DOI: 10.3310/GJRP0919

Organisation Name: NIHR Health Services and Delivery Research programme

Contact Address: NIHR Journals Library, National Institute for Health and Care Research, Evaluation, Trials and Studies Coordinating Centre, Alpha House, University of Southampton Science Park, Southampton SO16 7NS, UK

Contact Name: journals.library@nihr.ac.uk

Contact Email: journals.library@nihr.ac.uk