Adaptation, reliability and validity of health-related quality of life questionnaires: Disabkids chronic and specific diabetes disease in children and adolescents with diabetes mellitus type 1.

INTRODUCTION: It is recommended to periodically evaluate the health-related quality of life (HRQoL) in children and adolescents with type 1 diabetes mellitus (DM1). Despite this, no specific paediatric HRQoL instrument for DM1 has been validated in Spanish. OBJECTIVES: Multicentre, prospective descriptive study in children and adolescents with DM1 with the aim of carrying out cross-cultural adaptation to Spanish and evaluating the reliability and validity of the DISABKIDS chronic disease and diabetes-specific HRQoL questionnaires, using reverse translation. MATERIAL AND METHODS: Sociodemographic variables were compiled together with the most recent capillary glycated haemoglobin (HbA1c) value and HRQoL questionnaires were handed out to 200 Spanish children and adolescents with DM1 aged between 8 and 18 years of age under evaluation in 12 different hospitals. RESULTS: The mean score on the HRQoL questionnaire (patient version) for chronic disease was 80.32 (13.66), being significantly lower (P = .04) in patients with a shorter duration of the disease (≤5 years): 78.34 (13.70) vs. 82.60 (13.36). The mean score of the DM1-specific modules was: 60.81 (16.23) for disease impact and 65.59 (26.19) for treatment impact. The mean HbA1c value was 7.08 (0.79), with no differences (P > .05) noted in the mean score of the HRQoL instruments in patients with HbA1c ≤7% vs. HbA1c >7%. The Cronbach α value varied between 0.72 and 0.90. CONCLUSIONS: The Spanish versions of the DISABKIDS HRQoL instruments meet the proposed objectives of semantic equivalence and internal consistency, making it possible to periodically assess HRQoL in these patients. The good average glycaemic control presented by the patients may explain why no difference was found in the HRQoL instruments based on the HbA1c value.