Validation and Reliability of the French Version of the Sydney Swallow Questionnaire

Oropharyngeal dysphagia is frequently under-reported and early detection may lead to adapt strategies of rehabilitation and management decisions. The Sydney Swallow Questionnaire (SSQ), a self-reported questionnaire for the detection and quantification of oropharyngeal dysphagia, was previously adapted and validated in other languages but not in French. The purposes of this study were to develop and validate a French version of SSQ (SSQ-f) and to assess its psychometric properties. This SSQ-f, obtained by back-translation and cross-cultural adaptation, was validated in 27 patients with impaired swallowing and 27 healthy controls. After inclusion, patients filled in the SSQ-f and performed a videofluoroscopic swallow study. The penetration aspiration scale (PAS) and Dysphagia outcome and severity scale (DOSS) were assigned to assess construct validity. Sensitivity and specificity of cut-off scores for the SSQ-f were assessed by the receiver operating characteristic (ROC) curves. Moreover, the SSQ-f was repeated after 2 weeks to evaluate its test-retest reliability. The results supported that SSQ-f was considered understandable. Its total score was strongly correlated to the DOSS (r = - 0.873) and to the PAS (r = 0.738). It demonstrated acceptable internal consistency, with Cronbach's alpha values ranging from 0.744 to 0.956. The test-retest reliability was excellent. According to the ROC curve, cut-off scores of 118.5 or 218.5 were proposed for determining oropharyngeal dysphagia using DOSS as a reference and 755.0, using PAS as reference. No ceiling or floor effects were observed. In conclusion, the SSQ-f is a valid and reliable instrument to measure and detect oropharyngeal dysphagia in French-speaking subjects and can be used in a clinical setting.