RESUMEN
INTRODUCTION: Cystic Fibrosis (CF) is the most frequent chronic hereditary disease in the white race. Although the impact on the quality of life of this disease is significant, there are no validated instruments in the Chilean population to measure it. OBJECTIVE: To carry out a cultural and linguistic adaptation and validate the content and reliability of the CFQ-R Cystic Fibrosis Questionnaire, Spanish version 2.0. PATIENTS AND METHOD: The process was carried out in two stages. The first stage consists of an ins trumental design to adapt it culturally and linguistically, evaluate content validity by consulting ex perts, and test the comprehension of the questionnaire in patients and parents through qualitative interviews and a focus group. In the second stage with an observational and cross-sectional design in a sample of 122 people with CF or their caregivers, the behavior of the questionnaire was analyzed using descriptive statistics and Cronbach's alpha for reliability. RESULTS: Stage 1: the instrument in its three versions is considered valid with Lynn's index > 0.8 and Validity Coefficient > 0.7. Stage 2: The adolescent/adult and parent/caregiver versions obtain Cronbach's a > 0.7 and an average > 3 in most dimensions. CONCLUSION: The questionnaire is adapted and validated in the Chilean population and requires minor modifications. This version is reliable, valid, and allows the assessment of the quality of life in people with CF. It is suggested to increase the sample for the analysis of construct validity with a larger number of patients.