The value of a wound score for diabetic foot infections in predicting treatment outcome: a prospective analysis from the SIDESTEP trial.

Scoring the severity of a diabetic foot wound infection may help assess the severity, determine the type and urgency of antibiotic and surgical treatment needed, and predict clinical outcomes. We developed a 10-item diabetic foot infection wound score (results could range from 3 to 49 [least to most severe]) incorporating semi-quantitative grading of both wound measurements and various infection parameters. Using data from a prospective diabetic foot infection antibiotic trial (SIDESTEP), we evaluated the score's accuracy in predicting outcome, analyzed its components and tested it for consistency, construct, and validity. Wound scores for 371 patients significantly correlated with the clinical response; it was favorable at the follow-up assessment in 94.8% with a baseline score 19. Scores demonstrated good internal consistency (Cronbach's alpha >0.70 to <0.95). Patients with more severe wounds had higher scores, supporting construct validity. Excluding scores for wound discharge (purulent and nonpurulent), leaving an eight-item score, provided better measurement statistics. This easily performed wound score appears to be a reliable, valid, and useful tool for predicting clinical outcomes. Further validation studies in different patient populations should refine the items included.