The Activities-specific Balance Confidence scale: reliability and validity in Spanish patients with vestibular disorders

Purpose: To examine the reliability and validity of the Spanish version of the Activities-specific Balance Confidence scale (ABC-S), and its ability to discriminate between patients with and without a history of falls among a Spanish population with vestibular disorders. Method: A total of 84 participants completed the ABC-S. Internal consistency, test–retest reliability and construct validity (exploratory factor analysis) were analysed. Concurrent validity was evaluated using the 12-item Short Form Health Survey (SF-12) and the Dizziness Handicap Inventory (DHI). To determine the accuracy of the ABC total score in discriminating patients with and without a history of falls, a receiver operating characteristic (ROC) curve analysis was performed. Results: The ABC-S showed excellent internal consistency (Cronbach’s α?=?0.916) and substantial test–retest reliability (ICC?=?0.86, 95% CI: 0.74–0.93), with standard error and minimal detectable change values of 8.64 and 16.94, respectively. Factor analyses suggested a three-factor structure (explained variance was 62.24%). The ABC total score significantly correlated with the physical component summary score of the SF-12 and with the DHI-P, DHI-E, DHI-F and DHI total scores (p?p?Conclusions: The ABC-S is a valid and reliable instrument, suitable to assess balance confidence in Spanish patients with vestibular disorders.

• Implications for Rehabilitation

• The Spanish version of the ABC scale is a valid and reliable measure of balance confidence in patients with vestibular disorders.

• In persons with vestibular disorders, the Spanish version of the ABC scale has shown the ability to discriminate between patients with and without a history of falls in the last year.