Reliability of the Community Balance and Mobility Scale (CB&M) in high-functioning school-aged children and adolescents who have an acquired brain injury.
PRIMARY OBJECTIVE
To examine inter-rater, intra-rater and test-re-test reliability of the Community Balance and Mobility Scale (CB&M) and compare reliability in live vs videotape rating contexts for children with acquired brain injury (ABI).


RESEARCH DESIGN
Repeated measures design.


METHODS AND PROCEDURES
Seven physiotherapists (PTs) were trained as assessors. The primary assessor administered and scored baseline CB&M while the second assessor observed and scored independently (inter-rater reliability). Re-assessment occurred 3-10 days later by primary assessor (test-re-test reliability). Assessments were videotaped.


MAIN OUTCOMES AND RESULTS
There were 32 participants with ABI (mean age = 14 years 1 month (SD = 2 years 1 month)). Baseline mean scores were 67.4% (18.2) and 66.7% (18.3) for primary and second assessor, respectively. Primary assessors' re-test mean score was 69.3%. Inter-rater reliability ICC was 0.93 (95% confidence interval (CI) = 0.87-0.97). Test-re-test ICC was 0.90 (95%CI = 0.81-0.95) and Bland-Altman plot indicated greatest test-re-test differences for mid-range CB&M scores. Minimum detectable change (MDC₉₀) was 13.5% points.


CONCLUSIONS
The CB&M showed excellent reliability in youth. Reliability was comparable for live and videotape rating approaches, meaning that the easier and less expensive live-rating can be recommended. Future work should focus on evaluation of responsiveness to change in rehabilitation centre and community intervention contexts.