An investigation into the minimum accelerometry wear time for reliable estimates of habitual physical activity and definition of a standard measurement day in pre-school children

作者：Hislop Jane^*; Law James; Rush Robert; Grainger Andrew; Bulley Cathy; Reilly John J; Mercer Tom

来源：Physiological Measurement, 2014, 35(11): 2213-2228.

DOI：10.1088/0967-3334/35/11/2213

• physical activity
• pre-school
• measurement
• reliability
• accelerometry

The purpose of this study was to determine the number of hours and days of accelerometry data necessary to provide a reliable estimate of habitual physical activity in pre-school children. The impact of a weekend day on reliability estimates was also determined and standard measurement days were defined for weekend and weekdays. %26lt;br%26gt;Accelerometry data were collected from 112 children (60 males, 52 females, mean (SD) 3.7 (0.7) yr) over 7 d. The Spearman-Brown Prophecy formula (S-B prophecy formula) was used to predict the number of days and hours of data required to achieve an intraclass correlation coefficient (ICC) of 0.7. The impact of including a weekend day was evaluated by comparing the reliability coefficient (r) for any 4 d of data with data for 4 d including one weekend day. %26lt;br%26gt;Our observations indicate that 3 d of accelerometry monitoring, regardless of whether it includes a weekend day, for at least 7 h d(-1) offers sufficient reliability to characterise total physical activity and sedentary behaviour of pre-school children. These findings offer an approach that addresses the underlying tension in epidemiologic surveillance studies between the need to maintain acceptable measurement rigour and retention of a representatively meaningful sample size.

• 出版日期2014-11