Tele-Assessment of the Berg Balance Scale: Effects of Transmission Characteristics

OBJECTIVE: To compare Berg Balance Scale (BBS) rating using videos with differing transmission characteristics with direct in-person rating. DESIGN: Repeated-measures study for the assessment of the BBS in 8 configurations: in person, high-definition video with slow motion review, standard-definition videos with varying bandwidths and frame rates (768 kilobytes per second [kbps] videos at 8, 15, and 30 frames per second [fps], 30 fps videos at 128, 384, and 768 kbps). SETTING: Medical center. PARTICIPANTS: Patients with limitations (N=45) in ≥1 of 3 specific aspects of motor function: fine motor coordination, gross motor coordination, and gait and balance. INTERVENTIONS: Not applicable. MAIN OUTCOMES MEASURES: Ability to rate the BBS in person and using videos with differing bandwidths and frame rates in frontal and lateral views. RESULTS: Compared with in-person rating (7%), 18% (P=.29) of high-definition videos and 37% (P=.03) of standard-definition videos could not be rated. Interrater reliability for the high-definition videos was .96 (95% confidence interval, .94–.97). Rating failure proportions increased from 20% in videos with the highest bandwidth to 60% (P