Validation of the Japanese translation of the Swallowing Disturbance Questionnaire in Parkinson's disease patients

Abstract

Purpose: The Swallowing Disturbance Questionnaire (SDQ) was developed as a self-rated screening tool for dysphagia in patients with Parkinson's disease (PD). We developed the Japanese version of this questionnaire (SDQ-J), according to the cross-cultural adaptation guidelines, and examined its reliability.

Methods: Subjects were 61 Japanese patients with PD (mean age, 67.0 ± 9.2 years) who answered the SDQ-J before undergoing videofluoroscopic examination of swallowing (VF). We compared the findings of the questionnaire with the patients' aspiration status during VF.

Results: Cronbach's alpha coefficient for the 15 questions of the SDQ-J was 0.84. According to the SDQ-J, 15 patients (24.6%) were diagnosed with dysphagia, while 9 patients (14.8%) aspirated liquid during VF. The sensitivity and specificity of the SDQ-J in predicting aspiration were 77.8 and 84.6%, respectively; therefore, the SDQ-J significantly predicted aspiration during VF (P < 0.01). The positive predictive value (PPV) and negative predictive value (NPV) for the SDQ-J were 0.46 and 0.96, respectively.

Conclusions: The SDQ-J appears to be a reliable and useful screening tool for Japanese PD patients with aspiration. As the NPV was higher than the PPV in the SDQ-J, this questionnaire could potentially be used for early identification of severe dysphagia in patients with PD.