RATIONALE: Demands on healthcare workers are high: services are stretched, shifts are long and healthcare professionals (HCPs) regularly work lengthy periods without a break. Spending time continuously 'on task' changes decision-making in predictable ways, as described by the 'decision fatigue' phenomenon where decision-makers progressively shift towards making less cognitively effortful decisions as the time worked without a break increases. This phenomenon has been observed repeatedly in large quantitative observational studies, however, individual healthcare workers' experiences have not been explored. AIMS: This qualitative study aimed to explore general practitioners' (GPs) and advanced nurse practitioners' (ANPs) experiences of working for lengthy periods in an out-of-hours primary care service in the UK. This included exploration of self-perceived changes in decision-making throughout a work shift, and mitigating strategies used to avoid changes in decision-making over time. DESIGN: Semi-structured interviews were conducted online. An inductive thematic analysis was carried out to identify salient issues articulated by participants. SETTING AND PARTICIPANTS: The interview sample (n = 10) comprised ANPs (n = 5) and GPs (n = 5) who regularly worked within the out-of-hours primary care service across a regional National Health Service (NHS) health board. RESULTS: HCPs (GPs and ANPs) provided insights into their experiences during lengthy shifts and the impact of prolonged periods of work on clinical decision-making. Four main themes were identified and developed: (1) HCPs are aware of decision fatigue effects over the course of a shift
(2) Multiple factors help and hinder stable decision-making quality
(3) HCPs deliberately use strategies to help keep the quality of their decision-making stable
and (4) HCPs are aware of contextual changes, likely related to the decision fatigue phenomenon. CONCLUSIONS: The findings of this study underscore the intricate interplay of personal, social and systemic factors in decision-making quality and highlight HCPs' deliberate efforts to mitigate decision fatigue's effects in practice.