Validity Study of Dynamic Balance Abilities Measure using a Smartphone

Abstract

PURPOSE: The purpose of this study was to investigate the validity of dynamic balance measurements using a smartphone. METHODS: Thirty subjects were selected out of Y-university students without fractures, operation history, and inflammatory arthritis who had not started regular exercise during the past three months. Their dynamic balance ability was measured by the Biodex Balance System (Biodex Medical Systems, Inc., USA) using smartphones. The smartphone utilized in this study was the Galaxy Note4 LTE (SM-N910K, Samsung, Korea), and the application was the Sensor Kinetics pro (Ver.2.1.2, INNOVENTIONS Inc, US). The dynamic balance ability was measured in triplicate. RESULTS: With eyes closed, a low level of correlation (r>0.30, p0.60) were determined between the roll value of the smartphone gyroscope versus the medial/lateral score of the Biodex Balance System. With eyes closed, a low level of correlation (r>0.30, p0.60) were determined between the total value of the smartphone gyroscope versus the total score of the Biodex Balance System. CONCLUSION: This study indicated that using a smartphone can generate highly limited data regarding balance ability. They are unlikely to replace the existing more expensive devices entirely. However, smartphones may be highly useful in environments in which an expensive device is not available or when dynamic balance ability should be measured immediately or within a few hours.