Comparison of the information provided by electronic health records data and a population health survey to estimate prevalence of selected health conditions and multimorbidity. by Violán, C, Foguet-Boreu, Q, Hermosilla-Pérez, E, Valderas, J, Bolíbar, B, Fàbregas-Escurriola, M, Brugulat-Guiteras, P, Muñoz-Pérez, M