Effect of family medicine residents on use of diagnostic investigations: in a rural community emergency department.

OBJECTIVE: To determine the effect of the presence of family medicine residents on the use of laboratory and imaging investigations in a rural emergency department (ED).
DESIGN: A retrospective cross-sectional electronic chart audit was completed. Background characteristics, as well as type and number of ordered investigations, were compared between study groups.
SETTING: Strathroy Middlesex General Hospital in Strathroy, Ont, a rural community hospital that sees approximately 20 000 ED visits per year. PARTICIPANTS: A total of 2000 sequential ED visits, including adult and pediatric patients. The test group consisted of patients seen while a resident was present in the ED. The control group consisted of patients seen while no residents were present in the ED. MAIN OUTCOME MEASURES: Twenty-two distinct categories of common ED investigations were studied.
RESULTS: There was no statistically significant difference between study groups for 19 of the 22 categories of investigations. There were significant differences in 3 categories: an increased number of D-dimer assays for patients seen while there were no residents in the ED (1.7% of patients vs 0.5% of patients, P = .03) and increased computed tomography and ultrasound imaging for patients seen while a resident was in the ED (4.8% vs 1.8%, P = .0012, and 5.3% and 1.7%, P < .001, respectively). These differences are likely not owing to resident involvement but are explained by a difference in test availability between groups.
CONCLUSION: The study was underpowered for most categories of studied investigations. However, the trends demonstrated in this study suggest that the presence of family medicine residents in a rural community ED does not substantially affect the overall use of diagnostic investigations. Copyright© the College of Family Physicians of Canada.