Reproducibility and smallest real differences of walking and Energy Expenditure Index in children and adolescents with an acquired brain injury

BACKGROUND: Reliable evaluation is of utmost importance to the therapist and the patient. There is no data about the test-retest reproducibility of 6-Minute Walk Test (6MWT) and Energy Expenditure Index (EEI) for children and adolescents with an Acquired Brain Injury (ABI) in the sub-acute phase. OBJECTIVE: To determine test-retest reproducibility and smallest real differences (SRDs) of the 6MWT and EEI in children and adolescents with an ABI during rehabilitation in the sub-acute phase. Our second aim was to assess the correlation between the objective measure, the EEI, and the subjective perception of physical exertion obtained by using the pictorial children's effort rating scale (PCERT). METHODS: Twenty eight participants (12.5±4.3 years; 10 females) with an ABI in the sub-acute phase were asked to perform the 6MWT twice during their hospitalization. Heart rate was monitored during rest and throughout the 6MWT to calculate the EEI. Intra-class correlation coefficients (ICCs) and SRDs of the 6MWT and EEI were determined. RESULTS: Test-retest reproducibility was excellent for the 6MWT (ICC=0.98, SRD=65.73 m) and EEI tests (ICC=0.99, SRD=0.65 beats/m). Excluding one participant who walked extremely slowly resulted in ICC = 0.97, SRD = 67.01 m for the 6MWT, and ICC = 0.91, SRD = 0.25 beats/m for the EEI. No significant correlations were found between the EEI and PCERT. CONCLUSIONS: 6MWT and EEI are reliable measures in children and adolescents with an ABI during hospitalization in the sub-acute phase.