Measuring ambulation with wrist‐based and hip‐based activity trackers for children with cerebral palsy

• Published in: Developmental medicine and child neurology 2019-11, Vol.61 (11), p.1309-1313
• Main Authors: Sala, Debra A, Grissom, Helyn E, Delsole, Edward M, Chu, Mary Lynn, Godfried, David H, Bhattacharyya, Surjya, Karamitopoulos, Mara S, Chu, Alice
• Format: Article
• Language: English
• Subjects: Adolescent; Cerebral Palsy - diagnosis; Cerebral Palsy - physiopathology; Child; Child, Preschool; Female; Hip; Humans; Male; Monitoring, Ambulatory - instrumentation; Monitoring, Ambulatory - methods; Reproducibility of Results; Walking; Wrist
• ISSN: 0012-1622; 1469-8749
• DOI: 10.1111/dmcn.14207

Aim To assess the accuracy of consumer available wrist‐based and hip‐based activity trackers in quantitatively measuring ambulation in children with cerebral palsy (CP). Method Thirty‐nine children (23 males, 16 females; mean age [SD] 9y 7mo [3y 5mo]; range 4–15y) with CP were fitted with trackers both on their wrist and hip. Each participant stood for 3 minutes, ambulated in a hallway, and sat for 3 minutes. The number of steps and distance were recorded on trackers and compared to manually counted steps and distance. Pearson correlation coefficients were determined for the number of steps during ambulation from each tracker and a manual count. Mean absolute error (MAE) and range of errors were calculated for steps during ambulation for each tracker and a manual count and for distance for each tracker and hallway distance. Results For the number of steps, a weak inverse relationship (r=−0.033) was found for the wrist‐based tracker and a strong positive relationship (r=0.991) for the hip‐based tracker. The MAE was 88 steps for the wrist‐based and seven steps for the hip‐based tracker. The MAE for distance was 0.06 miles for the wrist‐based and 0.07 miles for the hip‐based tracker. Interpretation Only the hip‐based tracker provided an accurate step count; neither tracker was accurate for distance. Thus, ambulation of children with CP can be accurately quantified with readily available trackers. What this paper adds Consumer available activity trackers accurately measure ambulation in children with cerebral palsy (CP). The hip‐based tracker is more accurate than the wrist‐based tracker for children with CP. The hip‐based Fitbit activity tracker accurately measures step counts of children with CP during ambulation. Resumen Medición de la ambulación con rastreadores de actividad de muñeca y cadera para niños con parálisis cerebral Objetivo Evaluar la precisión de los rastreadores de actividad basados ​​en la muñeca y en la cadera disponibles para el consumidor en la medición cuantitativa de la ambulación en niños con parálisis cerebral (PC) Metodo Treinta y nueve niños (23 varones, 16 mujeres; edad media [DS] 9 años y 7 meses [3 años y 5 meses]; rango 4‐15 años) con PC fueron equipados con rastreadores en su muñeca y cadera. Cada participante se paró durante 3 minutos, caminó por un pasillo y se sentó durante 3 minutos. La cantidad de pasos y la distancia se registraron en los rastreadores y se compararon con los pasos y la distancia contados manualmente. Los