Cross-cultural adaptation and validation of the Portuguese version of the Living with Asthma Questionnaire

Objective: to translate and culturally adapt the living with asthma questionnaire (lwaq) to the portuguese language and to test its reliability and validity. methods: the portuguese version of this disease-specific health-related quality of life measure was obtained with forward/backward translations,consensus panels and a pre-test. the portuguese lwaq and medical outcomes study - 36 item short form (sf-36) questionnaires,and a form for the characteristics of the patients were administered to 61 subjects with asthma. results: reliability of lwaq scores was good with cronbach's alpha coefficients ranging from 0.70 to 0.97 [with the exception of «preoccupation»(0.62) construct,and «sleep»(0.67) and «effects on others»(0.47) domains] and intraclass correlation coefficients between 0.86 and 0.99. construct validity was supported by the confirmation of predefined hypotheses involving expected significant correlations between lwaq total,constructs and domains,and sf-36 dimensions with similar content. conclusion: the portuguese lwaq exhibited suitable psychometric properties,in terms of internal consistency,reproducibility and construct validity. © 2012 sociedade portuguesa de pneumologia.