Randomization and treatment regime used in our study.
A commercially available alcohol + PVP-I–based skin disinfectant (Braunoderm®, B. Braun, Melsungen, Germany) was used as a colored disinfectant, and Schülke-Optics (Schülke & Mayr, Norderstedt, Germany) was used as a colorless solution. Schülke-Optics contains among other ingredients IPA and is used for training and for review because it can be visualized using an UV lamp under darkened conditions (