This study aimed to provide a means for calibrating raw acceleration
data from wrist-worn accelerometers in relation to past estimates of children_s moderate-to-vigorous physical activity (MVPA) from a
range of cut points applied to hip-worn ActiGraph data. Methods: This is a secondary analysis of three studies with concurrent 7-d
accelerometer wear at the wrist (GENEActiv) and hip (ActiGraph) in 238 children age 9–12 yr. The time spent above acceleration
(ENMO) thresholds of 100, 150, 200, 250, 300, 350, and 400 mg from wrist acceleration data (e5-s epoch) was calculated for comparison
with MVPA estimated from widely used children_s hip-worn ActiGraph MVPA cut points (Freedson/Trost, 1100 counts per
minute; Pate, 1680 counts per minute; Evenson, 2296 counts per minute; Puyau, 3200 counts per minute) with epochs of e5, 15, and 60 s.
Results: The optimal ENMO thresholds for alignment with MVPA estimates from ActiGraph cut points determined from 70% of the
sample and cross validated with the remaining 30% were as follows: Freedson/Trost = ENMO 150+ mg, irrespective of ActiGraph epoch
(intraclass correlation [ICC] Q 0.65); Pate = ENMO 200+ mg, irrespective of ActiGraph epoch (ICC Q 0.67); Evenson = ENMO
250+ mg for e5- and 15-s epochs (ICC Q 0.69) and ENMO 300+ mg for 60-s epochs (ICC = 0.73); Puyau = ENMO 300+ mg for e5-s
epochs (ICC = 0.73), ENMO 350+ mg for 15-s epochs (ICC = 0.73), and ENMO 400+ mg for 60-s epochs (ICC = 0.65). Agreement was
robust with cross-validation ICC = 0.62–0.71 and means within Æ7.8Æ% T 4.9% of MVPA estimates from ActiGraph cut points, except
Puyau 60-s epochs (ICC = 0.42). Conclusion: Incremental ENMO thresholds enable children_s acceleration data measured at the wrist to
be simply and directly compared, at a group level, with past estimates of MVPA from hip-worn ActiGraphs across a range of cut points.