Comparison of ActiGraph GT9X Link with two Japanese accelerometers for assessments of free-living physical activity in junior high school students

Objective: This study compared the measurements of total steps and moderate-to-vigorous physical activity (MVPA) between ActiGraph and the Lifecorder and Active Style Pro accelerometers in junior high school students. Results: The total steps and MVPA significantly differed between ActiGraph and Lifecorder measurements, whereas the intraclass correlation coefficients (ICCs) for total steps and MVPA between the two accelerometers were not significant. There was no significant difference between the total steps measured using ActiGraph and Active Style Pro, and moderate agreement was noted. Additionally, MVPA measured using ActiGraph and Active Style Pro significantly differed, whereas the ICC for MVPA measured using the two accelerometers was not significant. When comparing the total steps between ActiGraph and Lifecorder and MVPA between ActiGraph and Lifecorder or Active Style Pro, it should be noted that the accelerometer measurements are not compatible.