Development of a Visual Analogue Scale questionnaire for subjective assessment of salivary dysfunction

Objective. This study's objective was to develop a Visual Analogue Scale (VAS) xerostomia questionnaire and to evaluate the validity and reliability for the clinical diagnosis of salivary gland dysfunction. Study design. Thirty-six healthy adults participated in this double-blind, crossover study. Each subject received an antisialagogue (glycopyrrolate) or placebo. Unstimulated and stimulated parotid and submandibular saliva samples were collected 16 times over a period of 6 hours. An 8-item VAS xerostomia questionnaire was administered after each saliva collection. Results. The results demonstrated significant reliability for 7 of the 8 VAS items, whereas validity was significant for unstimulated submandibular saliva. Moving averages were calculated for VAS and salivary flow rate values, and significant correlations were observed between these factors, indicating that changes in VAS responses were predictive of changes in salivary flow. Conclusions. These findings suggest that this VAS xerostomia questionnaire may be helpful in the diagnosis of salivary dysfunction and for detecting changes in salivary flow rate values over time.