1. Unit of Biostatistics, Department of Statistics, Mathematical Analysis, and Optimization; School of Medicine University of Santiago de Compostela; C/ San Francisco s/n 15782 Santiago de Compostela Spain
2. Faculty of Psychology and Education Sciences; University of Coimbra, CINEICC, Rua do Colégio Novo; Apartado 6153 3001-802 Coimbra Portugal
3. Institute of Statistics and Econometrics, Department of Economics; Georg-August-Universität Göttingen; Humboldtallee 3 37073 Göttingen Germany
4. Faculty of Medicine; University of Coimbra; Rua Larga 3004-504 Coimbra Portugal