[Cross-cultural adaptation and validation for Portuguese (Brazil) of health related quality of life instruments specific for gastroesophageal reflux disease].

BACKGROUND: Gastroesophageal reflux disease has been shown patients to alter quality of life and working productivity. Most of the instruments available for this type of assessment come from English or French speaking countries. To use these instruments in Brazil requires a judicious process of translation and validation.

AIM: Translating to Portuguese the questionnaires GSAS (Gastroesophageal Reflux Disease Symptom Assessment Scale), GERD-HRQL (Gastroesophageal Reflux Disease - Health Related Quality of Life) and HBQOL (Heartburn Specific Quality of Life Instrument) specific for quality of life assessment in gastroesophageal reflux disease. Testing the psychometric properties of reliability and validity of the referred disease specific instruments.

METHODS: One hundred and thirty two gastroesophageal reflux disease patients (mean age 54.9 years and +/- SD 13.9) from the Digestive Disease Motility Outpatient Clinic, Federal University of São Paulo, SP, Brazil and the Department of Surgical Gastroenterology "São José do Rio Preto" School of Medicine, São José do Rio Preto, SP, Brazil, accepted to participate and signed the informed consent form. Forty of these patients took part in the pre-test phase (28 females and 12 males, mean age 55.3 years +/- SD 14.7) and the remaining 92 part in the validation phase (64 females and 28 males, mean age 54.7 years and +/- SD 13.7). The translation and cultural adaptation processes were carried out accordingly us to the method of Guillemin et al (1993). The validation processes of the disease specific translated questionnaires (GSAS, GERD-HRQL and HBQOL) was performed in relation to a generic (SF-36) and a symptomatic (SQGERD) instrument.

RESULTS: Nine words of the GSAS, four of the GERD-HRQL and six of the HBQOL were replaced during the cultural adaptation phase. The GSAS questionnaire was discontinued after this phase because of scoring problems. Therefore reliability and validity were tested only for the two remaining questionnaires. These questionnaires proved to be reproducible for both inter and intra-observer relationships (0.980 and 0.968 values for the GERD-HRQL and varying values of 0.868 to 0.972 for the HBQOL). The HBQOL questionnaire demonstrated high internal consistency (>0.70) for three of the four dimensions tested (physical aspect, pain, sleep). Good correlations levels with the SF-36 and SQGERD questionnaires were demonstrated during the validation phase.

CONCLUSIONS: The cross cultural adaptation of the Portuguese (Brazil) versions of the GERD-HRQL and HBQOL instruments proved to be reliable and valid options with low burden level for assessment of quality of life in gastroesophageal reflux disease our country. The HBQOL is the only multidimensional questionnaire for quality of life assessment in gastroesophageal reflux disease currently available in Brazil. The Portuguese (Brazil) version of the GSAS instrument proved inadequate for quality of life assessment in our country.