126 patients scheduled for arthroscopic rotator cuff repair were randomized to one of four shoulder skin preparation methods: a solution or 1% chlorhexidine gluconate and 70% isopropyl alcohol with or without an antibacterial adhesive drape, or a solution of povidone-iodine with or without an antibacterial adhesive drape. The purpose of this study was to determine if skin preparation with chlorhexidine plus a drape demonstrated a significantly lower rate of Propionibacterium acnes (P. acnes) suture colonization compared to the other three groups. Compared to the povidone-iodine without drape group, the chlorhexidine plus drape group demonstrated a significantly lower incidence of positive culture identification. Statistical comparisons to the other two groups were not made.