Randomization and blinding
The researchers used a simple randomization technique. An external researcher generated the randomization assignment using a computer random number generator in Excel 2011 (version 14.0.0) and kept the assignments on a specific computer for this study. The group assignments were inaccessible to the rest of the staff. Neither the participants nor the investigators responsible for enrolling the patients could foresee the assignment because of the central allocation used for this study. To ensure that the assessment of the patients was not biased, we used an external assessor who was blinded to their group assignment.