How do practice-based pharmacists manage uncertainty when reviewing polypharmacy? Extending our understanding through a critical literature review and qualitative interviews

Abstract Introduction Clinical pharmacists currently represent the largest single group of professionals employed through Primary Care Networks in England. A key role of these pharmacists is to review patients with polypharmacy. The inherent clinical uncertainty associated with polypharmacy review can make decision-making difficult. Low tolerance of clinical uncertainty could incline pharmacists to avoid making deprescribing interventions and instead make no changes to patients’ medication regimens. Little is known about how pharmacists navigate clinical uncertainty or what interventions could support them to effectively review complex polypharmacy in primary care. Aim To understand the factors and available interventions that could mitigate clinical uncertainty, and in turn improve polypharmacy medication reviews. Methods Two separate studies were undertaken. Firstly, a critical literature review (CINAHL, Embase, MEDLINE and PsycInfo databases) was conducted in December 2023, including articles in the previous 20 years exploring polypharmacy, clinical uncertainty, medication review and deprescribing by primary care clinical pharmacists. Results were thematically analysed and two new conceptual models produced. Secondly, online semi-structured interviews were carried out with practice-based pharmacists. Participants were recruited from social media posts and purposively sampled for diversity of experience, qualifications, ethnicities and locations across England. The topic guide was based on findings from the literature review, exploring how pharmacists navigate uncertainty in polypharmacy review. Interview transcripts were coded inductively and deductively, using the Hillen Uncertainty Tolerance model.1 Dual coding was used to validate themes and develop a codebook. Thematic analysis was undertaken, facilitated by NVivo. Results 647 articles were screened; 11 (3xfocus group, 4xinterview, 2xethnography, 1xpilot cRCT and 1xintervention-development studies) were included. The novel conceptual models arising from the literature review explored i) factors affecting how pharmacists make decisions when experiencing clinical uncertainty and ii) determinants which affect deprescribing behaviour in medication reviews. The analysis of 20 practice-based pharmacist interviews produced a third model: an expanded Uncertainty Tolerance model, identifying new external moderators of clinical uncertainty. These new models explore internal cognitive, behavioural and emotional factors; internal factors which affect how pharmacists behave when experiencing uncertainty include fear of judgement and of being wrong, prescribing etiquette, and trust. External moderators of uncertainty tolerance include workplace cultures, informal peer support networks, physical location when providing clinical services, modality of encounter (face-to-face/remote), patient behaviour and senior colleague availability. Patient deference compounded clinical uncertainty in polypharmacy reviews, whereas equitable engagement and shared decision-making reduced uncertainty. Training and education can significantly moderate clinical uncertainty; this includes formal learning through postgraduate courses and informal learning in-practice via clinical supervision, group/peer learning and multidisciplinary case-based discussions. Conclusion This study has expanded the Hillen Uncertainty Tolerance model and highlighted the role of multidisciplinary working in mitigating clinical uncertainty. This study is limited in its scope by focussing on primary care settings in England only. The study’s strengths are its use of established critical literature review methodology2 and of pre-existing theoretical frameworks1 to interpret results. These findings have direct implications for how pharmacist-led polypharmacy reviews are delivered in general practice and how they can be optimised to ensure appropriate deprescribing is better facilitated.