The brachial plexus outcome measure: development, internal consistency, and construct validity.

PURPOSE: The purpose of this article was to report the development of a new assessment tool, the Brachial Plexus Outcome Measure (BPOM) and the evaluation of its internal consistency and construct validity.

METHODS: A retrospective case series of children aged 4-19 years with obstetrical brachial plexus palsy (OBPP) was conducted. Intraclass coefficients were calculated for the BPOM Activity Scale items. Correlation between the Active Movement Scale (AMS) and BPOM Activity Scale scores were conducted to determine the convergent validity.

RESULTS: The BPOM Activity Scale items (N=306) had good internal consistency (Cronbach's α=0.87). A strong correlation between the BPOM Activity Scale and AMS (n=284) was found (r=0.71, p=0.001, α=0.05).

CONCLUSIONS: The BPOM Activity Scale demonstrates good internal consistency and construct validity as a discriminative functional outcome measure in children with OBPP.

LEVEL OF EVIDENCE: IV.