Estimating Operating Room Time Improves Medicare Billing

Currently, physician fees for surgical services furnished to Medicare beneficiaries are largely governed by the resource-based relative value scale. Under this framework, relative value units (RVUs) are used to measure the physician time and effort associated with a particular procedure. While the RVU system is useful because it permits comparisons across procedures and specialties, it is not without flaws. Most significantly, it is subject to both over and under-valuation of procedures which may systematically distort compensation levels across specialties.

Accurately determining the work required to perform a given operation has implications for a variety of Medicare initiatives such as . In an era of increasing access to data, there may be more innovative and informative methods of measuring physician work rather than the traditional RVU survey-based valuation. One recent study evaluated the utility of estimation surgical procedure times from anesthesia billing data.

The authors linked Medicare billing data for anesthesia and surgical claims. This permitted them to associate anesthesia time (i.e. the time it took to complete a specific operation such as an appendectomy) with surgical Current Procedural Terminology (CPT) codes that defined the operation. Using clinical data from the National Surgical Quality Improvement Project (NSQIP), they were then able to create an adjustment factor to transform anesthesia time into total operative time.

This article demonstrates a novel method of gleaning more accurate and policy-relevant information using existing data. In an era of increasingly granular electronic data, it is likely that other areas of health care will find similar ways of answering quality and cost questions without the need for a cumbersome infrastructure specifically designed to collect data.

Accurate measurement of surgical time using billing data opens the door for several future lines of inquiry such as determining the significance of hospital and provider level variation in operating room time, determining which procedures are better measured using time versus existing RVUs, and providing better estimates of procedural complexity.

commentary by Andrew Gonzalez

Abstract

OBJECTIVE: The median time required to perform a surgical procedure is important in determining payment under Medicare’s physician fee schedule. Prior studies have demonstrated that the current methodology of using physician surveys to determine surgical times results in overstated times. To measure surgical times more accurately, we developed and validated a methodology using available data from anesthesia billing data and operating room (OR) records.

DATA SOURCES: We estimated surgical times using Medicare 2011 anesthesia claims and New York Statewide Planning and Research Cooperative System 2011 OR times. Estimated times were validated using data from the National Surgical Quality Improvement Program. We compared our time estimates to those used by Medicare in the fee schedule.

STUDY DESIGN: We estimate surgical times via piecewise linear median regression models.

PRINCIPAL FINDINGS: Using 3.0 million observations of anesthesia and OR times, we estimated surgical time for 921 procedures. Correlation between these time estimates and directly measured surgical time from the validation database was 0.98. Our estimates of surgical time were shorter than the Medicare fee schedule estimates for 78 percent of procedures.

CONCLUSIONS: Anesthesia and OR times can be used to measure surgical time and thereby improve the payment for surgical procedures in the Medicare fee schedule.

PMID: 26952688  Burgette, LF, et al. HSR. 2016 Mar 8; epub ahead of print.