Risk Adjustment Instruments in Administrative Data Studies: A Primer for Neurosurgeons.

ABSTRACT

With the increasing interest in big data and health services research, use of administrative databases is becoming commonplace in health care studies, including in neurosurgery. Administrative data offer the unique advantage of accessing large amounts of information previously collected from a population-based sample with geographic diversity. When using administrative data sets, researchers can benefit from application of risk adjustment instruments, which help stratify patients and tailor the original sample for specific research questions. The Charlson Comorbidity Index and Elixhauser Comorbidity Index are 2 of the most common indices. The Pediatric Medical Complexity Algorithm and Clinical Classification Software are other promising tools. Understanding of these tools may assist neurosurgeons who wish to critically assess research findings relevant to their clinical practice. In this review, an overview is presented of risk adjustment tools commonly used in adult as well as pediatric populations and their history, uses, limitations, and applications in neurosurgical research are summarized.