Introduction: The importance of early recognition and treatment of Sepsis has been emphasized over the last several years. In an attempt to better prioritize these patients, the Canadian Triage and Acuity Scale (CTAS) revised the adult temperature modifier after 2008 to define fever as 38.0C or higher and apply SIRS criteria, appearance and immunocompromise to assign a CTAS level of 2, 3, or 4. Prior to 2008, the fever threshold was defined as 38.5C and SIRS criteria were not included. This study looks to see if these changes increased the sensitivity of the temperature modifier. Methods: This study is a retrospective cohort analysis of patients presenting with a temperature of <36.0C or >38.0C to six Edmonton-area EDs in calendar years 2008 (n=26181) and 2012 (n=51622). Outcomes of interest included the temperature modifier predicted score and the actual assigned CTAS score. Data was extracted from the HASS/iSoft EDIS database including: presenting complaint, vital signs, CTAS score, and applied CTAS modifier to generate a before and after comparison of the actual and theoretical impact of temperature modifier revisions on the CTAS score, for both time periods. Results: Applying the pre-2008 temperature modifier to the 2008 patient cohort assigned 11.5% to CTAS 2, 39.8% to CTAS 3, and 33.3% to CTAS 4. Applying the post-2008 revised temperature modifier assigned 22.2% CTAS 2, 41.9% CTAS 3, and 27.6% CTAS 4. Carrying out the same analysis on the 2012 patients pre- results were 12.4% CTAS 2, 46.4% CTAS 3, 30.2% CTAS 4; and the post results were 21% CTAS 2, 47.7% CTAS 3, and 25% CTAS 4. Differences between pre- and post-results were statistically significant (p<0.0001) in both years. The actual triage scores in 2012 were 18.7% CTAS 2 indicating the temperature modifier was not always correctly applied and 50.6% CTAS 3 as other modifiers were sometimes applied. Conclusion: There was a significant increase in sensitivity following the post 2008 revisions to the CTAS temperature modifier when applied to two large ED patient cohorts. The differences between theoretical and actual CTAS scores was less dramatic as nurses were able to apply other first order or special modifiers to assign an appropriate score. Further analysis will be carried out to determine the impact of the temperature modifier revisions on time to antibiotic and admission rates.