The Gothenburg Trismus Questionnaire in China: Cross-cultural adaptation and measurement invariance.

Objectives: The Gothenburg Trismus Questionnaire (GTQ) is a comprehensive scale for screening and assessing trismus in head and neck (H&N) cancer and temporomandibular joint disorders (TMD) patients. This study aimed to translate and cross-culturally adapt the GTQ in China, and to test its measurement invariance.

Methods: This study comprised 278 H&N cancer, 245 TMD, and 507 control patients. Internal consistency and test-retest reliability were tested to assess the GTQ's reliability. The validity was evaluated through composite reliability (CR), average variance extracted (AVE), and correlation tests. Multi-group confirmatory factor analysis (CFA) was used to investigate the GTQ's measurement invariance across clinical status and gender. T tests were employed to compare score differences across clinical status and gender.

Results: The Chinese version of GTQ scale shows excellent internal consistency and test-retest reliability. The CR, AVE, and correlation values demonstrate the good validity of GTQ. The multi-group CFA supported configural invariance across clinical status but not metric invariance, while it supported strict invariance across gender. Additionally, t tests revealed that patients with H&N cancer and TMD scored higher than the control group, while males scored higher than females.

Conclusions: The Chinese version of GTQ serves as an effective tool for screening and assessing trismus.