Clinical Frailty Scale and Charlson Comorbidity Index as predictors of hospitalization and mortality risk after kidney transplant failure Rita Leal; Pedro Almiro e Castro; Rui Duarte; Ana Rita Silva; Maria Guedes Marques; Luís Rodrigues; Lídia Santos; Catarina Romãozinho; Helena Oliveira Sá; Arnaldo Figueiredo; Rui Alves;