RT Journal Article SR Electronic T1 O-016 Comparing validated stroke screening scales for identifying large- and medium-vessel occlusions: a prospective, observational cohort study JF Journal of NeuroInterventional Surgery JO J NeuroIntervent Surg FD BMJ Publishing Group Ltd. SP A11 OP A11 DO 10.1136/jnis-2024-SNIS.16 VO 16 IS Suppl 1 A1 Kothari, S A1 Morsi, R A1 Baskaran, A A1 Sehgal, N A1 Metman, O A1 Desai, H A1 Thind, S A1 Chahine, A A1 Zakaria, J A1 Karar, L A1 Penagos, J A1 Siegler, J A1 Coleman, E A1 Mendelson, S A1 Brorson, J A1 Prabhakaran, S A1 Kass-Hout, T YR 2024 UL http://jnis.bmj.com/content/16/Suppl_1/A11.2.abstract AB Introduction/Purpose Rapid pre-hospital identification of acute ischemic stroke secondary to large-vessel occlusions (AIS-LVO) has proven to be successful in interhospital transfers and triaging patients. Although there are multiple stroke screening scales available, their utilization varies significantly across diverse settings. This study aims to compare the diagnostic validity of 8 different stroke screening scales in screening for AIS-LVO and AIS secondary to medium-vessel occlusions (AIS-MeVO).Materials and Methods We prospectively analyzed all stroke alert activations at a single tertiary academic center between January 2022 and December 2023. We prospectively applied 8 stroke screening scales (BE-FAST, LAMS, PASS, FAST-ED, EMS RACE, 3-ISS, VAN, and NIHSS) to each stroke alert in both the emergency department and inpatient settings. The final diagnosis was classified as AIS-LVO or AIS-MeVO, AIS without LVO or MeVO, intracranial hemorrhage, transient ischemic attack, and stroke mimic.Results Of 221 patients where all 8 stroke screening scales were performed, 199 patients were ultimately examined to compare pre-hospital validated anterior circulation LVO scales in the emergency department (ED) and in-hospital settings for both large- and medium-vessel occlusions. The mean age was 63.8 ± 15.2 years, 62.3% were female (n=124), and 84.4% were African American/Black (n=168). The LAMS scale had the highest performance (AUC: 0.750 [95% CI: 0.668 to 0.831]), closely followed by the FAST-ED (AUC: 0.736 [95% CI: 0.649 to 0.822]), and VAN (AUC: 0.735 [95% CI: 0.651 to 0.818]) scales. Cutoff points selected from coordinates of the ROC curves for these scales were 3, 3, and a positive VAN.Conclusion This is the first, prospective cohort study comparing the performance of 8 different screening scales among stroke alerts in the ED and inpatient settings for the detection of both AIS-LVO and AIS-Me *, VO. We found LAMS to be the most sensitive tool for detection of AIS-LVO and AIS-MeVO, followed by FAST-ED and VAN.Disclosures S. Kothari: None. R. Morsi: None. A. Baskaran: None. N. Sehgal: None. O. Metman: None. H. Desai: None. S. Thind: None. A. Chahine: None. J. Zakaria: None. L. Karar: None. J. Penagos: None. J. Siegler: None. E. Coleman: None. S. Mendelson: None. J. Brorson: None. S. Prabhakaran: None. T. Kass-Hout: None.