ABSTRACT NUMBER: ESOC2026A1815 VARIABILITY IN MANUALLY REGISTERED DOOR TIME: IMPLICATIONS FOR STROKE QUALITY METRICS

Abstract Background and aims Time-based workflow metrics, such as door-to-needle time, are key quality indicators in acute ischemic stroke (AIS) care. These metrics often depend on manual registration of timepoints such as the “door time”, which are and inconsistently defined and registered. We aimed to assess inter-rater variability in manually registered door time across routinely used data sources. Methods We conducted a retrospective cross-sectional study of IVT-treated patients with AIS suspicion admitted to Stavanger University Hospital between March 2017 and September 2023. Patients with independently documented door time in both nursing and physician records were included, and the two sources were compared. Within-patient variability was assessed using median (interquartile range; IQR) and mean absolute differences (standard deviation; SD) Results Of 2,008 eligible patients, 405 (20%) had complete data from both sources. The median absolute difference in door time within the same patient was 2.0 minutes (IQR: 1.0–5.0), while the mean was 9.7 minutes (SD: 45.5 minutes). The distribution was significantly right skewed with outliers, and normality tests confirmed non-normality. Conclusions Manually registered door time varies considerably between documentation sources referring to the same index event, highlighting important limitations in the reliability of door-to-needle metrics. The observed discrepancies alone approach the magnitude of treatment-time improvements targeted by many stroke quality initiatives, making awareness of these discrepancies essential for correct interpretation of registry data. Clear operational definitions and standardised, robust time-stamping approaches, including automated solutions, may be warranted to ensure accurate and comparable quality metrics in acute stroke care. Conflict of interest Trym Kolstø. Nothing to disclose. Nedim Leto. Nothing to disclose. Soffien Ajmi. Nothing to disclose. Martin Kurz. Nothing to disclose.