RESUMEN
INTRODUCTION: EMS systems use call prioritization to distinguish between high and low acuity patients, better use resources, and set system response times. Previous research focused on patient condition; however, recent research has reviewed patient acuity as an important maker for system response. Our objective was to analyze any trend between priority dispatch determinant codes and using a red lights and siren (RLS) transport from the scene. METHODS: Retrospective cohort observational study of 9-1-1 calls received in CY 2003. Chi-square analysis for trend and odds ratios with 95% CI were calculated to evaluate the differences in proportions of patients being transported RLS from the scene according to determinant level, p < 0.05 was considered significant. RESULTS: There was significant heterogeneity among the determinant cohorts (chi-square = 204.477, p < 0.001, 5 df). Further analysis showed absolute and proportional increases in RLS transport from the scene with increasing determinant level. The three lowest determinant levels were low risk (OR 0.13, 0.49, and 0.58), and the two highest determinant levels had significant risk for RLS transport (OR 1.63, 32.11). CONCLUSIONS: Patients had increasing likelihood of being transported by RLS from the scene with increasing determinant level. Calls with the two highest determinant levels were at significant risk of being transported RLS from the scene.