Validation of the Center for Neurologic Study Bulbar Function Scale-Chinese version in a population with amyotrophic lateral sclerosis.

OBJECTIVE: The Center for Neurologic Study Bulbar Function Scale (CNS-BFS) was specifically designed as a self-reported measure of bulbar function. The purpose of this research was to validate the Chinese translation of the CNS-BFSC as an effective measurement for the Chinese population with ALS. METHODS: A total of 111 ALS patients were included in this study. The CNS-BFSC score, three bulbar function items from the ALSFRS-R, and visual analog scale (VAS) score for speech, swallowing and salivation were assessed in the present study. Forty-six ALS patients were retested on the same scale 5-10 days after the first evaluation. RESULTS: The CNS-BFSC sialorrhea, speech and swallowing subscores were separately correlated with the VAS subscores (p < 0.001). The CNS-BFSC total score and sialorrhea and speech scores were significantly correlated with the ALSFRS-R bulbar subscore (p < 0.001). The CNS-BFSC total score and ALSFRS-R bulbar subscale score were highly predictive of a clinician diagnosis of impaired bulbar function (area under the receiver operating characteristic curve, 0.947 and 0.911, respectively; p < 0.001). A cutoff value for the CNS-BFSC total score was selected by maximizing Youden's index; this cutoff score was 33, with 86.4% sensitivity and 93.3% specificity. The CNS-BFSC total score and the sialorrhea, speech and swallowing subscores had good-retest reliability (p > 0.05). The Cronbach's α of the CNS-BFSC was 0.972. CONCLUSION: The Chinese version of the CNS-BFSC has acceptable efficacy and reliability for the assessment of bulbar dysfunction in ALS patients.

Assessment of bulbar function in amyotrophic lateral sclerosis: validation of a self-report scale (Center for Neurologic Study Bulbar Function Scale).

BACKGROUND AND PURPOSE: Impaired bulbar functions of speech and swallowing are among the most serious consequences of amyotrophic lateral sclerosis (ALS). Despite this, clinical trials in ALS have rarely emphasized bulbar function as an endpoint. The rater-administered Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised (ALSFRS-R) or various quality-of-life measures are commonly used to measure symptomatic benefit. Accordingly, we sought to evaluate the utility of measures specific to bulbar function in ALS. METHODS: We assessed bulbar functions in 120 patients with ALS, with clinicians first making direct observations of the degree of speech, swallowing and salivation impairment in these subjects. Clinical diagnosis of bulbar impairment was then compared with ALSFRS-R scores, speech rate, time to swallow liquids and solids, and scores obtained when patients completed visual analog scales (VASs) and the newly-developed 21-question self-administered Center for Neurologic Study Bulbar Function Scale (CNS-BFS). RESULTS: The CNS-BFS, ALSFRS-R, VAS and timed speech and swallowing were all concordant with clinician diagnosis. The self-report CNS-BFS and ALSFRS-R bulbar subscale best predicted clinician diagnosis with misclassification rates of 8% and 14% at the optimal cut-offs, respectively. In addition, the CNS-BFS speech and swallowing subscales outperformed both the bulbar component of the ALSFRS-R and speech and swallowing VASs when correlations were made between these scales and objective measures of timed reading and swallowing. CONCLUSIONS: Based on these findings and its relative ease of administration, we conclude that the CNS-BFS is a useful metric for assessing bulbar function in patients with ALS.