Anderson Cheryl B, Hagströmer Maria, Yngve Agneta
Department of Pediatrics, Baylor College of Medicine, The Children's Nutrition Research Center, Houston, TX 77030, USA.
Med Sci Sports Exerc. 2005 Jul;37(7):1224-30. doi: 10.1249/01.mss.0000170073.57440.df.
To evaluate the validity of the Previous Day Physical Activity Recall (PDPAR) as a physical activity diary in adolescents using two accelerometer intensity classifications.
One hundred eighth graders (47 boys, 53 girls) used the PDPAR as a daily diary and wore MTI accelerometers for four consecutive days. Measured time spent in moderate (> or = 3 METs) and vigorous (> or = 6 METs) activity was based on two published MTI cut-point limits (that of Freedson et al./Trost et al. and that of Puyau et al.). Spearman rank order correlations and Bland-Altman plots were used to examine agreement between MTI and PDPAR diary estimates of activity.
MTI estimates of mean minutes per day of total moderate to vigorous physical activity (MVPA) were 65.2 (+/-43.2) using the Freedson et al./Trost et al. cutoffs and 17.5 (+/-18.5) using those of Puyau et al., while students self-reported 105.1 (+/-80.1) min.d(-1). Significant relationships were observed between the diary and MTI for total MVPA using either the Freedson et al./Trost et al. (r = 0.42) or Puyau et al. (r = 0.41) cutoff as well as raw counts (r = 0.44). Plots showed reasonable agreement between the diary and Freedson et al./Trost et al. MTI estimates of MVPA for daily totals of < or = 60 min, but the Puyau et al. estimates were consistently lower. Diaries overestimated activity as time increased when compared to either MTI cut point, especially on vigorous activity.
Time estimates of MVPA differed by assessment tool, but diary estimates showed adequate association with the MTI. Diaries reflected intensity-specific activity, corresponding most closely with the Freedson et al./Trost et al. classification of moderate, but substantially overestimated vigorous activity regardless of cut-point method. This is likely due to the measurement characteristics of the PDPAR, which classifies activities in 30-min blocks, as well as the nature of common activities in which high levels of intensity are not sustained.
使用两种加速度计强度分类方法评估前一天身体活动回忆法（PDPAR）作为青少年身体活动日记的有效性。
100名八年级学生（47名男生，53名女生）将PDPAR用作每日日记，并连续四天佩戴MTI加速度计。根据已发表的两种MTI切点限值（Freedson等人/Trost等人的以及Puyau等人的）来测量中度（≥3代谢当量）和剧烈（≥6代谢当量）活动所花费的时间。使用Spearman等级相关和Bland-Altman图来检验MTI与PDPAR日记对活动估计值之间的一致性。
使用Freedson等人/Trost等人的切点时，MTI对每天中度至剧烈身体活动（MVPA）总分钟数的估计为65.2（±43.2），使用Puyau等人的切点时为17.5（±18.5），而学生自我报告为105.1（±80.1）分钟·天⁻¹。使用Freedson等人/Trost等人（r = 0.42）或Puyau等人（r = 0.41）的切点以及原始计数（r = 0.44）时，日记与MTI之间在总MVPA方面均观察到显著关系。图表显示，对于每日总计≤60分钟的MVPA，日记与Freedson等人/Trost等人的MTI估计值之间具有合理的一致性，但Puyau等人的估计值始终较低。与任何一种MTI切点相比，随着时间增加，日记对活动的估计值都被高估，尤其是在剧烈活动方面。
MVPA的时间估计因评估工具而异，但日记估计值与MTI显示出足够的相关性。日记反映了特定强度的活动，与Freedson等人/Trost等人的中度分类最为接近，但无论采用何种切点方法，都大幅高估了剧烈活动。这可能是由于PDPAR的测量特性，它以30分钟为单位对活动进行分类，以及常见活动的性质，即高强度水平无法持续。
