1. Nursing Department, Medical School, São Paulo State University (Unesp), Botucatu, Brazil.
2. School of Nursing, University of Campinas (Unicamp), Campinas, Brazil.
3. Medical Clinic Department, Medical School, São Paulo State University (Unesp), Botucatu, Brazil.
4. Biostatistics Department, Institute of Biosciences, São Paulo State University (Unesp), Botucatu, Brazil.