1. Departament of Coloproctology, Faculty of Medicine, Universidade de Mogi das Cruzes, Mogi das Cruzes, SP, Brazil
2. Medical school, Universidade de Mogi das Cruzes, Mogi das Cruzes, SP, Brazil
3. Department of Surgery, Universidade de São Paulo, São Paulo, SP, Brazil
4. Graduate Studies in Health Sciences, Universidade de São Francisco, Bragança Paulista, SP, Brazil
5. Department of Surgery, Faculty of Medical Sciences, Universidade Estadual de Campinas, Campinas, SP, Brazil
6. Statistics, Universidade de Mogi das Cruzes, Mogi das Cruzes, SP, Brazil