The Standardized Infection Ratio (SIR), developed by the National Healthcare Safety Network (NHSN), is a validated healthcare quality outcome measure utilized by the California Department of Public Health (CDPH). Our primary goal was to use information from the SIR as measures of risk-adjusted surgical case-mix complexity and Healthcare Associated Infection (HAI) quality for surgical site infections (SSIs) in hip prosthesis (HPRO) surgery. We acquired NHSN SSI data files for HPRO surgery from 330 acute care hospitals. We categorized hospitals into 5 types (teaching, rural, community low volume, community medium volume, and community high volume) and sorted hospitals by procedure count, generating volume terciles. We multiplied each SIR and 95% confidence limits by a scale factor to allow for a comparison to the average SIR in California for the study period. The highest and lowest expected infection rates (case-mix complexity) were found in teaching hospital (0.86%) and community, high- volume hospitals (0.56%). When all non-teaching hospitals were combined, teaching hospitals treated a higher case complexity (95% Confidence Limit (CL): 0.7713 to 0.9727) than non-teaching hospitals (95% CL 0.5774, 0.6518). The lowest and highest SIR values were seen in community high volume (0.78) and rural hospitals, (1.38). The lowest- volume hospitals performed significantly worse (SIR 1.15: 95%CL 1.058-1.256) than the highest- volume hospitals (SIR 0.83: 95% CL 0.747-0.920). The SIR model developed by NHSN provides important public information about risk-adjusted surgical case-mix complexity and hospital quality for SSIs that incorporates parameters that may more accurately account for technical challenges in HPRO surgery.