Validity of wrist worn accelerometers and comparability between hip and wrist placement sites in estimating physical activity behaviour in preschool children

Abstract

Wrist-worn accelerometers can increase compliance with wearing accelerometers, however, several large scale studies continue to use hip-worn accelerometers and it is unclear how comparable data is from the two sites. The study aims were: to investigate agreement between wrist-and hip-worn accelerometers and to determine the validity of Johansson et al cut-points for wrist worn accelerometers in preschool children.A sample of 32 preschool children (21 boys, 4.2 (0.5) years, BMI 16.6 (1.1)) were videoed wearing GT3X+ accelerometers on their wrist and hip while they engaged in 1 hour of free-play in their nursery.Children's activity were coded using, the Children's Activity Rating Scale (CARS): with CARS, level 1 'sedentary' and levels 2 to 5 were classified as time spent in TPA. Accelerometry data were processed using Johansson et al cut-points for the wrist data and Evenson et al cut-points for the hip data, into time spent in different intensities of PA. The mean counts per minute (cpm) from the hip and wrist were compared.There was a strong correlation between the hip and wrist cpm (r=0.81, p<0.01) and total count data (r=0.83 p<0.01), however there was a large systematic bias with wide limits of agreement. Good agreement (mean difference (LOA) 1.1 (-9.9, 12.1) was found between the CARS estimate of TPA (29.

Examining accelerometer validity for estimating physical activity in pre‐schoolers during free‐living activity

“…Therefore, further research to find ways to optimize wrist-based accelerometry for MVPA levels would be beneficial as compliance is increased at this location. 22 The cut points derived from the current study are comparable to some previously published for this age group. 23 used direct observation criterion methods similar to the current study.…”

“…These results indicate that a combination of accelerometer placements may be most accurate for estimating both PA and SB in the pre‐school age population, as SB and MVPA are important when measuring children's overall PA levels. Therefore, further research to find ways to optimize wrist‐based accelerometry for MVPA levels would be beneficial as compliance is increased at this location . The cut points derived from the current study are comparable to some previously published for this age group.…”

“…Previous literature has reported that wear time and compliance are increased when monitors are worn on the wrist . However, hip‐worn ActiGraph accelerometers are more accurate for measuring PA .…”

“…Previous literature has reported that wear time and compliance are increased when monitors are worn on the wrist. 22 However, hip-worn ActiGraph accelerometers are more accurate for measuring PA. 7 Current findings in this study also support this in respect to MVPA, whereas SB and LPA were measured more accurately by wrist-located devices. As previously stated, direct observation has been considered a robust and in-depth method to classify the intensity of PA and the context in which it takes place.…”

Accelerometer-Based Physical Activity Levels Differ between Week and Weekend Days in British Preschool Children

“…As mentioned, it could be questioned whether wearing the accelerometer on the wrist is suitable for preschool children. Research has looked at the difference between wearing a wrist and hip accelerometer on preschool children and one study in Scotland found that wrist-worn accelerometers provided a valid estimate of total physical activity, whereas hip-worn accelerometers showed a reasonable agreement to cut-points [68]. This was supported by a study in Stockholm, Sweden, which similarly monitored preschool children and found that wrist-worn accelerometers performed more accurately when assessing time spent in sedentary, light activity and MVPA, when compared to hip-worn accelerometers [69].…”