Reliability and validity of the Chinese version of Global Sleep Assessment Questionnaire in adult patients with sleep disorders

Objective: This study aimed to translate Global Sleep Assessment Questionnaire (GSAQ) in Chinese and to validate it in adult patients with sleep disorders. Methods: GSAQ was translated following the steps of scale translation. Two hundred and one adult patients (aged over 18 years old) with sleep disorders were recruited. All filled out the 11-item Chinese version of GSAQ. The translated version was tested by exploratory factor analysis (EFA), confirmatory factor analysis (CFA), criterion validity, Cronbach’s α and spilt-half reliability. To evaluate the predictive ability of the questionnaire and elicit cutoff values, receiver operating characteristic (ROC) curves were generated. Results: Out of the 11 questions in the questionnaire, each item was significantly correlated with the total score by a correlation coefficient (r) ranging from 0.24 to 0.73. Four factors were extracted explained 68.89% of the total variance. Cronbach’s α coefficient for the total scale of 11 items was 0.72 and for four factors was 0.81, 0.64, 0.76 and 0.72 respectively, with a split-half reliability of 0.75. ROC analysis yielded an AUC > 0.8. The “obstructive sleep apnea related”, “insomnia related”, “restless legs syndrome related”, and “parasomnias related” scores showed cutoff values of 3,3,1,1, respectively. The GSAQ had positive correlation with AHI (r = 0.248 p = 0.0025), insomnia severity index (r = 0.322, p = 0.017) and the rapid eye movement sleep behavior disorder screening questionnaire (r = 0.721, p