['To evaluate the effect of negative pressure wound therapy (NPWT) on deep infection rate in open tibial fractures.', 'Retrospective cohort study. Data was collected from medical records and radiographs.', 'Two level-1 trauma centers.', 'Patients who sustained an open tibial fracture which underwent delayed soft tissue coverage between January 2002 and December 2007 were included. Exclusion criteria included open fractures receiving a combination of NPWT and conventional dressings, fractures which were treated with a primary amputation, and fractures associated with mortality.', ": NPWT with reticulated open cell foam or conventional dressings at surgeon's discretion.", 'Deep infection rate.', 'A total of 229 open tibial fractures in 220 patients met the inclusion criteria and received either NPWT (166/229-72%) or conventional dressings (63/229-28%). There was a decreased rate of deep infection in the NPWT group compared with the conventional dressing group [8.4% (14/166) vs. 20.6% (13/63); P = 0.01]. Univariate predictors of deep infection included Gustilo type {odds ratio (OR): 3.13 [95% confidence interval (CI): 1.74-5.64]; P < 0.001} and use of NPWT [OR: 0.35 (95% CI: 0.16-0.80); P = 0.01]. When adjustment was performed for Gustilo type with multivariate analysis, use of NPWT was found to reduce the risk of deep infection by almost 80% [OR: 0.22 (95% CI: 0.09-0.55); P = 0.001].'] Does negative pressure wound therapy reduce deep infection rate in open tibial fractures?