Surveillance of Youth Physical Activity and Sedentary Behavior With Wrist Accelerometry

Abstract

Introduction Accurate tracking of physical activity (PA) and sedentary behavior (SB) is important to advance public health, but little is known about how to interpret wrist-worn accelerometer data. This study compares youth estimates of SB and moderate to vigorous PA (MVPA) obtained using raw and count-based processing methods. Methods Data were collected between April and October 2014 for the National Cancer Institute’s Family Life, Activity, Sun, Health, and Eating Study: a cross-sectional Internet-based study of youth/family cancer prevention behaviors. A subsample of 628 adolescents (aged 12–17 years) wore the ActiGraph GT3X+ on the wrist for 7 days. In 2015–2016, SB and MVPA time were calculated from raw data using R-package GGIR and from activity counts data using published cutpoints (Crouter and Chandler). Estimates were compared across age, sex, and weight status to examine the impact of processing methods on behavioral outcomes. Results ActiGraph data were available for 408 participants. Large differences in SB and MVPA time were observed between processing methods, but age and gender patterns were similar. Younger children (aged 12–14 years) had lower sedentary time and greater MVPA time (p-values <0.05) than older children (aged 15–17 years), consistent across methods. The proportion of youth with ≥60minutes of MVPA/day was highest with the Crouter methods (~50%) and lowest with GGIR (~0%). Conclusions Conclusions about youth PA and SB are influenced by the wrist-worn accelerometer data processing method. Efforts to harmonize processing methods are needed to promote standardization and facilitate reporting of monitor-based PA data.

Calibration and Validation of the Youth Activity Profile: The FLASHE Study

“…This finding was consistent with another study in this supplement examining PA patterns in a sample of more than 400 youth. 36 Previous research using hip-worn accelerometers and pedometers has consistently shown boys to be more active than girls so it is possible that the present findings may be influenced by the unique nature of the wrist-worn monitors. The decision to process the data using the Crouter et al 23 cut points was supported by a parallel study conducted as part of the FLASHE evaluation.…”

“…Estimates of SB and MVPA differed on average by 2 and 35 minutes/day, respectively. Another paper in this supplement 36 also revealed more-realistic PA patterns with the method of Crouter et al than with the GGIR method available to process raw ActiGraph data at the wrist. Additional research is still needed to determine the most appropriate ways to process wrist-worn data, but the main point is that the YAP estimates as described in this study are linked to the unique characteristics of both the monitor (i.e., GT3X+) and data processing methods (i.e., Crouter and colleagues’ method) used in the calibration.…”

The FLASHE Study: Survey Development, Dyadic Perspectives, and Participant Characteristics

“…A subsample of adolescents also wore accelerometers to provide an objective measure of their physical activity, as described elsewhere in this issue. 37,40,44 Though efforts were made to recruit a balanced sample, the FLASHE adult sample included more female than male participants and tended to be highly educated. 37 However, FLASHE recruited nationally and includes dyads from all states except Alaska.…”

Recruitment, Enrollment, and Response of Parent–Adolescent Dyads in the FLASHE Study

“…However, processing these data has been challenging given the field of physical activity epidemiology is just starting to develop the appropriate metrics for wrist-worn accelerometry data processing. 18 Third, the protocol tested the feasibility of collecting accelerometer data in a web-based, consumer panel framework where study administrators had no direct contact with participants and a limited number of monitors to utilize. It was unclear if participants would: (1) decline participation because of the additional requirements of the motion study protocol; (2) adhere to all aspects of the motion study protocol; and (3) return the monitor in a timely fashion.…”