Table 1.
Description of Actigraph studies and corresponding prediction equations and cut points
| Activity Protocola First Author, Publication Year (Methodb) |
Sample | Equation for metabolic costs in METs | Cut points for MET values |
|||
|---|---|---|---|---|---|---|
| Size (n) |
Sex | Agesc (years) |
Moderate (3 to 6) |
Vigorous (≥ 6) |
||
| Ambulatory Activities | ||||||
| Brage, 2003d | 12 | M | 23 – 30 | 2.886 + 0.0007429*counts/min−0.02*VO2 Study sample VO2 (=61.6)EQ1 |
1810 | 5850 |
| National Health and Nutrition Examination Survey laboratory sample VO2 (=43.2)EQ2 | 1316 | 5354 | ||||
| Freedson, 1998 | 50 | M/F | 24 ± 4 | 1.439008 + 0.000795*counts/min | 1952 | 5725 |
| Leenders, 2001 | 28 | M/F | 24 ± 4 | 2.240 + 0.0006*counts/min | 1267 | 6252 |
| Brooks, 2005 | 72 | M/F | 35 – 45 | 2.32 + 0.000389*counts/minEQ1 | 1748 | 9460 |
| 3.33 + 0.000370*counts/min−0.012*weightEQ2 | weight-specific | weight-specific | ||||
| Heil, 2003 | 58 | M/F | 28 ± 6 | 1.551 + 0.000619*counts/minEQ1 | 2341 | 7187 |
| −1.833 + 0.00171*counts/min + 1.957*height-0.000631*counts/min*heightEQ2 | height-specific | height-specific | ||||
| Yngve, 2003 | 28 | M/F | 23 ± 3 | 1.136 + 0.0008249*counts/minEQ1 | 2260 | 5896 |
| Yngve, 2003 | 28 | M/F | 23 ± 3 | 0.751 + 0.0008198*counts/minEQ2 | 2743 | 6403 |
| Troiano, 2008e | n/a | n/a | n/a | Based on weighted average of cut points | 2020 | 5999 |
| Lifestyle Activities | ||||||
| Hendelman, 2000 | 25 | M/F | 30 – 50 | 2.922 + 0.000409*counts/min | 191 | 7526 |
| Matthews, 2005 | 19 | M/F | 19 – 29 | Based on distributional properties resulting from combined information from laboratory and field studies | 760 | 5725 |
| Swartz, 2000 | 70 | M/F | 19 – 74 | 2.608 + 0.0006863*counts/min | 574 | 4945 |
a
Activity protocol refers to the type of activities in which the cut points were derived: ambulatory (walking/running only) and lifestyle activities (for example, gardening, raking, vacuuming, and playing with children)
b
Method is the study-specific cut point
c
Age distribution from study is either a range (with ‘−‘) or the mean and standard deviation (with ‘± ‘)
d
Equation was converted from VO2·kg−1 to METs by dividing the parameters by 3.5 mL·kg−1·min−1
e
Troiano cut points are a weighted average of cut points from the Brage, Freedson, Leenders, and Yngve studies.