Measuring Surgical Access: The Correlation of Hospital and Patient-Focused Metrics

Treatment incidence ratios (TIRs), a patient-focused, procedure-based measure of surgical availability, are not associated with surgical workforce density. In this study, we evaluated the association between hospital- and patient-focused measures of surgical availability and nonlocal care.

We performed a retrospective analysis of the North Carolina inpatient admissions from 2016 to 2019. Hospital treatment rates (HTRs) for common surgical diseases were calculated by hospital, while TIRs (attributed to patient ZIP code) were calculated at the county and hospital service area (HSA) level. The association between HTRs and TIRs was estimated with adjusted linear regression modeling. The association between counties and HSAs with the lowest rates of surgery and the proportion of their residents receiving non-local care for urgent/emergent general surgical disease was estimated with adjusted linear regression.

Nearly 30% of the patients received non-local care. At the county and HSA level, HTRs were associated with TIRs. Patients in counties and HSAs with the lowest HTRs had 15.2% and 15.8% fewer surgeries per admission. Counties and HSAs with the lowest surgery rates had 17% and 14.4% higher proportion of non-local care for urgent/emergent general surgical diseases.

Despite 30% of the patients receiving nonlocal care, what local surgeons do may be more relevant to patient care patterns than how many surgeons there are.