Construct Validity of the Both Hands Assessment Using Wrist-Worn Accelerometers

AimThe aim of this study was to evaluate the construct validity of the Both Hands Assessment (BoHA) using activity of the upper limbs as detected by accelerometry in children with bilateral cerebral palsy (CP).MethodsObservational study of children with CP (n = 44, n = 27 boys, aged 9.1 +/- 1.6 years; Manual Ability Classification Scale I: n = 15, II: n = 22, III: n = 7) completing a BoHA assessment while wearing a triaxial accelerometer on each wrist. BoHA Each-Hand sub-scores, BoHA percentage difference between hands, BoHA Units, mean activity for each hand, mean activity asymmetry index and total mean activity were calculated. Linear regressions were used to analyze associations between measures.ResultsThere were significant, positive associations between BoHA Units and total mean activity (B = 0.86, 95%CI: 0.32, 1.40), BoHA Percentage difference between hands and mean activity asymmetry index (B = 0.95, 95%CI: 0.75,1.15), and BoHA Each-Hand sub-score and mean activity for the non-dominant hand (B = 1.71, 95%CI: 1.16, 2.28), but not the dominant hand (B = 0.50, 95%CI: -0.45, 1.45).ConclusionsThis study provides further evidence for the construct validity of the BoHA as a measure of upper limb performance. Wearable wrist sensors such as accelerometers capture and quantify gross upper limb movement in children with CP but cannot measure fine finger movements captured by the BoHA.