Burden of multimorbidity, socioeconomic status and use of health services across stages of life in urban areas: a cross-sectional study. - Violán, Concepción; Foguet-Boreu, Quintí; Roso-Llorach, Albert; Rodriguez-Blanco, Teresa; Pons-Vigués, Mariona; Pujol-Ribera, Enriqueta; Muñoz-Pérez, Miguel Ángel; Valderas, Jose M. (BMC Public Health, 2014)