TOLEDO GUTIÉRREZ, M. I.; ALARCÓN MUÑOZ, A. M.; BUSTOS MEDINA, L.; HEUSSER RISOPATRÓN, F.; HEBEL WEISS, E.; LORCA OSORIO, P.; CASTILLO NIÑO, M. E.; GARAY GREVE, F. Contribution of Qualitative Methods in the Validity of an Instrument which Measures Quality of Life Related to Health in Children Suffering from a Chronic Illness. Forum Qualitative Sozialforschung / Forum: Qualitative Social Research, v. 10, n. 2, 30 May2009.