Validation of the metrics properties of ‘UO Pharma’: a new French tool for measuring hospital pharmaceutical activity

Abstract Objectives In the French healthcare system, workload units (UO for ‘unités d’œuvre’) are essential for determining public hospital costs. Historically, ‘UO Pharma’ measured pharmacy activity with a single indicator, i.e. dispensed medication and medical devices, which did not reflect the complexity of hospital pharmacy tasks. A new version, introduced in 2021, adds 43 indicators alongside 14 related to specific activity for more accurate measurement. This study evaluates its validity and reliability. Methods A retrospective observational study analysed 2021 and 2022 UO Pharma data from the national hospital cost accounting database. Descriptive analyses evaluated UO Pharma adoption based on hospital characteristics, regions, and activity levels. Validity was assessed through convergent validity (correlation with hospital bed-days) and construct validity (exploratory factor analysis). Reliability was measured using Cronbach’s alpha for internal consistency and test–retest reliability via intraclass correlation coefficients. Key findings Approximately 20% of eligible hospitals used UO Pharma, with some regional and hospital-type variations. The tool demonstrated strong internal consistency (Cronbach’s alpha: 0.87 in 2021 and 0.89 in 2022), but some dimensions (e.g. medication dispensing) showed lower consistency (Cronbach’s alpha ≤ 0.6). Test–retest reliability showed excellent reliability (intraclass correlation coefficient > 0.90) for 12 of 35 items, with 13 items showing moderate to good reliability (>0.50). Convergent validity was confirmed with a strong correlation (r = 0.84), improving from 2021 (r = 0.26) to 2022 (r = 0.98). Conclusions UO Pharma is a reliable and valid tool. To improve user experience and understanding of some items, we recommend clarifications in the user guide for areas with identified confusion.