Natural and Exact Sciences Department, Higher School of Health Technology of Lisbon of Polytechnic Institute of Lisbon and Center of Statistics and Applications of University of Lisbon, Lisbon, Portugal. carina.silva@estesl.ipl.pt|Natural and Exact Sciences Department, Higher School of Health Technology of Lisbon of Polytechnic Institute of Lisbon and Center of Statistics and Applications of University of Lisbon, Lisbon, Portugal. carina.silva@estesl.ipl.pt|Natural and Exact Sciences Department, Higher School of Health Technology of Lisbon of Polytechnic Institute of Lisbon and Center of Statistics and Applications of University of Lisbon, Lisbon, Portugal. carina.silva@estesl.ipl.pt