Estimating Resource Utilization in Congenital Heart Surgery.

Background: Optimal methods to assess resource utilization in congenital heart surgery remain unclear. We compared traditional cost-to-charge ratio methods with newer standardized cost methods that aim to more directly assess resources consumed.

Methods: Clinical data from The Society of Thoracic Surgeons Database were linked with resource use data from the Pediatric Health Information Systems Database (2010 to 2015). Standardized cost methods specific to the congenital heart surgery population were developed and compared with cost-to-charge ratio methods. Resource use in the overall population and variability across hospitals were described using hierarchical mixed effect models adjusting for case-mix.

Results: Overall, 43 hospitals (65,331 patients) were included. There were minimal population-level differences in the distribution of resource use as estimated by the two methods. At the hospital level, there was less apparent variability in resource use across centers with the standardized cost vs cost-to-charge ratio method, overall (coefficient of variation 20% vs 25%) and across complexity (The Society of Thoracic Surgeons-European Association for Cardiothoracic Surgery [STAT]) categories. When hospitals were categorized into tertiles by resource use, 33% changed classification depending on which resource use method was used (26% by one tertile and 7% by two tertiles).

Conclusions: In this first evaluation of standardized cost methodology in the congenital heart population, we found minimal differences vs traditional methods at the population level. At the hospital level, the magnitude of variation in resource use was less with standardized cost methods, and approximately one third of centers changed resource use categories depending on the methodology used. Because of these differences, care should be taken in future studies and in benchmarking and reporting efforts in selecting optimal methodology.