Deviation-based cost modeling: a novel model to evaluate the clinical and economic impact of clinical pathways.

Background: Although clinical pathways were developed to streamline patient care cost efficiently, few have been put to rigorous financial test. This is important today, because payors demand clear solutions to the cost-quality puzzle. We describe a novel, objective, and versatile model that can evaluate and link the clinical and economic impacts of clinical pathways.

Study Design: Outcomes for 209 consecutive patients undergoing high-acuity surgery (pancreaticoduodenectomy), before and after pathway implementation, were examined. Four grades of deviation (none to major) from the expected postoperative course were defined by merging length of stay with a validated classification scheme for complications. Deviation-based cost modeling (DBCM) links these deviations to actual total costs.

Results: Clinical outcomes compared favorably with benchmark standards for pancreaticoduodenectomy. Despite increasing patient acuity, this new pathway shortened length of stay, reduced resource use, and decreased hospital costs. DBCM indicated that fewer deviations from the expected course occurred after pathway implementation. The impacts of complications were less severe and translated to an overall cost savings of $5,542 per patient. DBCM also revealed that as more patients migrated to the expected course within our standardized care path, 50% of overall cost savings ($2,780) was attributable to the pathway alone, and improvements in care over time (secular trends) accounted for the remainder.

Conclusions: DBCM accurately determined the incremental contribution of clinical pathway implementation to cost savings beyond that of secular trends alone. In addition, this versatile model can be customized to other systems' improvements to reveal their true clinical and economic impacts. This is valuable when choices linking quality with cost must be made.