Relative value units poorly correlate with measures of surgical effort and complexity

Abstract

Background: The relationship between procedural relative value units (RVUs) for surgical procedures and other measures of surgeon effort are poorly characterized. We hypothesized that RVUs would poorly correlate with quantifiable metrics of surgeon effort.

Methods: Using the 2010 American College of Surgeons - National Surgical Quality Improvement Program (NSQIP) database, we selected 11 primary current procedural terminology codes associated with high volume surgical procedures. We then identified all patients with a single reported procedural RVU who underwent nonemergent, inpatient general surgical operations. We used linear regression to correlate length of stay (LOS), operative time, overall morbidity, frequency of serious adverse events (SAEs), and mortality with RVUs. We used multivariable logistic regression using all preoperative NSQIP variables to determine other significant predictors of our outcome measures.

Results: Among 14,481 patients, RVUs poorly correlated with individual LOS (R(2) = 0.05), operative time (R(2) = 0.10), and mortality (R(2) = 0.35). There was a moderate correlation between RVUs and SAEs (R(2) = 0.79) and RVUs and overall morbidity (R(2) = 0.75). However, among low- to mid-level RVU procedures (11-35) there was a poor correlation between SAEs (R(2) = 0.15), overall morbidity (R(2) = 0.05), and RVUs. On multivariable analysis, RVUs were significant predictors of operative time, LOS, and SAEs (odds ratio 1.06, 95% confidence interval: 1.05-1.07), but RVUs were not a significant predictor of mortality (odds ratio 1.02, 95% confidence interval: 0.99-1.05).

Conclusions: For common, index general surgery procedures, the current RVU assignments poorly correlate with certain metrics of surgeon work, while moderately correlating with others. Given the increasing emphasis on measuring and tracking surgeon productivity, more objective measures of surgeon work and productivity should be developed.

Keywords: Adverse events; Length of stay; Morbidity and mortality; Operative time; Relative value units.