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<.001) in videos with the lowest bandwidth, with no significant differences in proportions across frame rate categories. Both frontal and lateral views were critical for successful rating using videos, with 60% to 70% (P<.001) of videos unable to be rated on a single view.

CONCLUSIONS

Although there is some loss of information when using videos to rate the BBS compared to in-person ratings, it is feasible to reliably rate the BBS remotely in standard clinical spaces. However, optimal video rating requires frontal and lateral views for each assessment, high-definition video with high bandwidth, and the ability to carry out slow motion review.