FIGURE 1.

Cumulative hazards for SSTI recurrence for the drainage subgroup. SSTIs were determined on the basis of a visit with a specific ICD-9-CM code (Supplemental Table 4) and a filled prescription for an antibiotic within 2 days. Recurrence was defined as fulfilling the same criteria (including a new antibiotic) between 15 and 365 days after the incident event. Drainage was determined on the basis of CPT and ICD-9-CM procedure codes (Supplemental Table 4) representing incision and drainage. HRs were estimated in Cox proportional-hazard regression analyses with adjustment for year, age, gender, race/ethnicity, and diagnosis.