Validity of three-day physical activity recording tools among adolescents with arranged schedule

Objective To develop a three-day physical activity recording tools suitable for young people in China by using accelerometer as the gold standard.Methods This study was conducted among 148 high school adolescents aged 12-17 years (70boys and 78 girls) in Beijing.All the adolescents were provided with the recording tool together with the ActiGraph GT3X + Accelerometer and returned it back a week later.Re-issue the recording tool to fill in the reliability test.Spearman correlation and the Bland-Altman graph was used to evaluate the association between the recording instrument and accelerometer.Retest reliability was evaluated by intra-class correlation coefficient.Results Spearman coefficient between the recording tool and the accelerometer was 0.246-0.557(P<0.05).Brian-Altman's consistent analysis showed that the consistency of MPA,VPA and MVPA results was 94.59%,95.27% and 93.24%,respectively,showing high validity.The intra-class correlation coefficients of the average daily metabolic equivalents (METS) between the two measurements were higher than 0.7,indicating good reliability of our recording tool.Conclusion The three-day physical activity recording tool developed in this study has good reliability and validity,and can be used to investigate the large-scale physical activity of adolescents.