Most surgeons' daily elective lists in Florida comprise only 1 or 2 elective cases, making percent utilization unreliable for planning individual surgeons' block time.

Study Objective: Operating room (OR) utilization has been shown in multiple studies to be an inappropriate metric for planning OR time for individual surgeons. Among surgeons with low daily caseloads, percentage utilization cannot be measured accurately because confidence limits are extremely wide. In Iowa, a largely rural state, most surgeons performed only 1 or 2 elective cases on their OR days. To assess generalizability, we analyzed Florida, a state with many high-population density areas.

Design: Observational cohort study.

Setting: The 602 facilities in Florida that performed inpatient or outpatient elective surgery from January 2010 through December 2019.

Subjects: The providers licensed to perform surgery in Florida (physician, oral surgeons, dentists, and podiatrists) were identified by their national provider number. Hospitals were deidentified before analysis.

Measurements: The primary endpoint was the mean among facilities in percentages of surgeon-day combinations ("lists") containing 1 or 2 cases. Proportions were calculated using Freeman-Tukey transformation and the harmonic mean of the number of lists at each facility. Comparison to "most" (>50%) used Student's two-sided one-group t-test.

Main Results: Averaging among hospitals, most surgeons' lists included 1 or 2 cases (64.4%; 99% confidence interval [CI] 61.3%-67.4%) P < 0.00001). Many lists had 1 case (44.2%, 99% CI 41.2%-47.2%). Nearly all (96.7%) surgeons operated at just one hospital on their OR days.

Conclusions: Most surgeons' lists of elective surgical cases comprised 1 or 2 cases in the largely urban state of Florida, as previously found in the largely rural state of Iowa. Results were insensitive to organizational size or county population. Thus, our finding is generalizable in the United States. Consequently, neither adjusted nor raw utilization should be used solely when allocating OR time to individual surgeons. Anesthesia and nursing coverage of cases can be based on maximizing the efficiency of use of OR time.