Table 2.

National Healthcare Safety Network Surgical Site Infection Basic Risk Index

Risk Points Assigned	Category	Reason for Assigning Points
1 point	Duration of surgery	If the operation lasts longer than the duration cutpoint, where the duration cutpoint is the 75th percentile of the duration of surgery in minutes for any particular operative procedure (defined as ≥ 56 min for cesarean delivery)
1 point	Class of wound	If the wound is categorized as contaminated (class 3) or dirty/infected (class 4)
1 point	Physical status of the patient	If the American Society of Anesthesiologists Classification of Physical Status (the patient’s preoperative medical status) is defined as class III, IV, or V

Data from Edwards JR et al.⁷