Validation of the Synkinesis Assessment Questionnaire

Abstract

Objective: To validate the Synkinesis Assessment Questionnaire (SAQ), a newly developed patient-graded instrument to evaluate facial synkinesis.

Study design: This was a prospective clinical questionnaire validation study.

Methods: A total of 65 patients with facial nerve disorders were recruited from the Facial Nerve Center. In 28 patients (group I), the SAQ, a preliminary 10-item instrument, was administered at the initial visit and repeated within 3 weeks without any medical or surgical intervention. In 37 patients (group II), the SAQ was administered before botulinum toxin therapy for facial synkinesis and again 2 weeks after Botox therapy. In addition, the instrument was administered to 20 healthy subjects without facial nerve dysfunction (group III). The reliability, validity, and responsiveness of the SAQ were assessed.

Results: Test-retest reliability for the SAQ was high (Spearman's rank correlation r = 0.876, P < .0001). Internal consistency of the instrument was assessed by calculating the Cronbach alpha value. This analysis supported the deletion of one item from the final SAQ. The Cronbach alpha for the final SAQ was 0.859. Construct validity analysis showed a statistically significant improvement in SAQ scores (P < .001) after successful administration of botulinum toxin for treatment of facial synkinesis. There was a highly statistically significant difference (P < .0001) in SAQ scores between normal subjects (group III) and patients with facial synkinesis (group II).

Conclusions: The SAQ is a simple, patient-graded instrument designed to assess facial synkinesis. Instrument analysis suggests that it is a reliable and valid instrument for the assessment of facial synkinesis. The validated SAQ is the first dedicated instrument designed to assess facial synkinesis.