The study retrospectively reviewed 1,029 general surgery operations performed from September 1, 1991 to May 31, 1993 to find out the association between the occurrence of surgical site infection (SSI) and the Centers for Disease Control-National Nosocomial Infection Surveillance (CDC-AWS) surgical patient risk index scores. The index assigned 1 point for each of 3 risk factors: 1) American Society of Anesthesiologists (ASA) preoperative assessment class 3, 4 or 5; 2) an operational classified as either contaminated or dirty-infected; 3) an operation with a duration longer than a specified increased with increasing contamination (p=0.000) as well as increasing index scores (p=0.000). Looking at operations within the same category of contamination, SSI rates also increased with increasing scores among clean operations (p=0.944), clean-contaminated operations (p=0.000), contaminated operations (p=0.559), and dirty operations. SSI rates in this hospital series were compared to the 44-hospital CDC-NNIS report.