Impact of Standardized Edmonton Symptom Assessment System Use on Emergency Department Visits and Hospitalization: Results of a Population-Based Retrospective Matched Cohort Analysis.

The Edmonton Symptom Assessment System (ESAS) is a validated instrument whose use has been standardized in the Ontario cancer system to measure symptoms among ambulatory patients with cancer. The objective was to examine the effect of ESAS exposure on visits to the emergency department (ED) and hospitalizations. This was a retrospective matched cohort study conducted in Ontario, Canada. The study included patients ≥ 18 years of age diagnosed with cancer between 2007 and 2015. Patients were considered exposed if they were screened with ESAS at least once during the study period, and their first ESAS screening date was defined as the index date. Each exposed patient was matched randomly to a patient with cancer without ESAS assessment using a combination of hard matching (birth year ± 2 years, cancer diagnosis date ± 1 year, cancer type, and sex) and propensity score matching (14 variables, including cancer stage, treatments received, and comorbidities). A multivariable Andersen-Gill recurrent event model was used to evaluate the effect of ESAS on the rate of health care use. The analysis included 128,893 matched pairs that were well balanced on baseline measures. After adjusting for other variables, patients with ESAS had lower rates of both ED visits (relative rate [RR], 0.92; 95% CI, 0.91 to 0.93) and hospitalizations (RR, 0.86; 95% CI, 0.85 to 0.87) compared with patients without ESAS. ESAS exposure is independently associated with decreased rates of ED visits and hospitalizations. This provides real-world evidence of one potential positive impact of standardized symptom assessment in cancer care.