Adaptation of the Asthma Quality of Life Questionnaire to a second language preserves its critical properties: The Spanish version

To test the metric proprieties of the Spanish version of the Juniper Asthma Quality of Life Questionnaire (AQLQ), we studied 116 adult asthmatic patie nts with a wide range of disease severity (53 patients were recruited from the respiratory outpatient department, 38 from a primary health care centre and 25 were patients admitted into hospital due to acute asthma). The pati ents were assessed twice, at recruitment and after 2 months. The AQLQ showe d a high internal consistency (Cronbach's alpha = 0.78 to 0.96) and a high 2-week reproducibility (ICC = 0.82 to 0.92). Expected significant differenc es in AQLQ scores were observed according to disease severity as measured b y symptoms, medication, use of services and recruitment setting. The cross- sectional and longitudinal correlations between AQLQ and the overall St. Ge orge's Respiratory Questionnaire were strong, moderate to strong between AQ LQ and dyspnea and weak to moderate between AQLQ and FEV,. The changes in A QLQ scores were significantly different in patients who either improved or deteriorated from those patients who remained stable (P < .0001 and P < .01 , respectively, for the overall AQLQ). We conclude that the Spanish version of the AQLQ is reliable, valid and sensitive to changes. (C) 2001 Elsevier Science Inc. All rights reserved.