Background 

Xerostomia is a common complication in patients with head and neck cancer (HNC) during and after radiotherapy. The lack of a simply-administered and well-validated self-reported instrument has hampered the assessment and management of xerostomia for research and clinical purposes in China.

Objective 

This study aimed to evaluate the content validity and psychometric properties of the Xerostomia Questionnaire (XQ) in Chinese patients with HNC undergoing radiotherapy.

Methods 

This psychometric evaluation study enrolled 80 patients and was conducted in 2 stages: translation and evaluation of content validity and psychometric evaluation. Cognitive interviews (n = 10) were conducted using the Participant Interview Form. The psychometric evaluation (n = 80) included score distribution, homogeneity (interitem and item-total correlations), factor structure (exploratory factor analysis), internal consistency (Cronbach’s α), criterion-related validity (person correlation), and test-retest reliability (intraclass correlations).

Results 

Content validity was supported by cognitive interviews. The factor analysis resulted in a 1-factor solution with strong factor loadings (0.84-0.91) that explained 75.6% of the total variance. The internal consistency was excellent, with a Cronbach’s α of .95. The XQ correlated strongly with other measures of xerostomia (0.70-0.80), which supports criterion-related validity. The test-retest reliability was excellent (intraclass correlation coefficient = 0.92).

Conclusions 

The result provides evidence for the validity and reliability of the XQ in a sample of Chinese patients with HNC.

Implications for Practice 

The XQ can be used in both clinical practice and research as a valuable tool to screen for problems with xerostomia, monitor the xerostomia level, and evaluate the effects of treatment and interventions among patients with HNC.