Value

Some of the measures in value-based purchasing programs may be flawed due to inadequate risk adjustment. The purpose of this study was to examine the effect of the surgical casemix on surgical site infection rates using combined colectomy–hepatectomy resections as a test case. We identified all adult patients undergoing elective colon surgery (2007–2013) in the National Inpatient Sample. We defined patients with a concurrent liver resection as “multivisceral resections.” Cases from each hospital were pooled by hospital identifier. The association between surgical site infection rate and the proportion of multivisceral resections performed was compared statistically. Findings were further tested for independence against hospital-level characteristics similar to risk-adjusted surgical site infection rate reporting. We identified 1014 hospitals performing 127,646 colon surgeries including 1168 (0.9%) multivisceral resections. The overall surgical site infection rate for multivisceral resection was 11.3% versus 1.6% for colectomy-only resections (p？<？0.001). Simple linear regression demonstrated a 2.3% increase in a hospital’s surgical site infection rate for each 1% increase in the proportion of multivisceral resections performed. Multivariable linear regression demonstrated a preserved association. A hospital’s rate of surgical site infections is positively associated with the proportion of multivisceral resections performed. Value-based purchasing programs should assess readily available data for further risk-adjustment inclusion