2. Materials and Methods
RS
RESOLUTION
The present study was a pilot, randomized, double-blind, placebo-controlled study conducted in Porto Alegre, RS, Brazil. The study was approved by the ethics and research committee of the Federal University of Health Sciences of Porto Alegre (UFCSPA), under approval number 4.031.047. The study follows the ethical precepts established by Resolution 196/96 of the National Health Council, which regulates ethics in research with human beings. The study protocol was designed and conducted in accordance with the Declaration of Helsinki, and all participants gave informed consent before participating in the study.The sample size calculation was determined using the Randomized Controlled Trials formula proposed by Chan (2003), as described in [