Table 3. Accelerometer-Derived Variables and Cut Point Definitions Used in Studies Published Since 2007 (or Forthcoming) on Accelerometer Data for Adults, National Health and Nutrition Examination Surveys, 2003–2004 and 2005–2006a .
| Accelerometer-derived variable | Cut point definition | Reference |
|---|---|---|
| Activity counts/d | Sum of daily activity counts | (13) |
| Mean activity counts/min | Sum of daily activity counts/number of min worn | (2,6,13,21,30,32,33,35,43,52) |
| Mean counts/min of most intense 10 min/wk | ≥2,020 Activity counts/min | (6) |
| Time in sedentary behaviors (any min) | <100 Activity counts/min | (3,7,10,11,13-15,17,19,21-23,29,30,33,43,49,52) |
| Steps in sedentary behaviors (any min) | Steps detected <100 activity counts/min | (12) |
| Time in sedentary behaviors (>5-min bouts) | <100 Activity counts/min | (29) |
| Time in sedentary behaviors (any min) | <260 Activity counts/min | (37,40) |
| Proportion of sedentary time | Proportion of valid wear time at <100 activity counts/min | (29,33) |
| Stillness | Average intensity during time <100 activity counts/min | (29) |
| Time in inactive intensity (any min) | 100–499 Activity counts/min | (12) |
| Steps in inactive intensity (any min) | Steps detected 100–499 activity counts/min | (12) |
| Time in low intensity (any min) | 100–499 Activity counts/min | (7,13,17) |
| Time in low intensity (any min) | 100–759 Activity counts/min | (43) |
| Time in lifestyle intensity (any min) | 760–2,019 Activity counts/min | (18,33,43,50) |
| Proportion of time in lifestyle intensity | Proportion of valid wear time at 760–2,019 activity counts/min | (18,33) |
| Steps in lifestyle intensity (any min) | Steps detected 760–2,019 activity counts/min | (18,50) |
| Proportion of steps/d in lifestyle activity | Proportion of steps/d at 760–2,019 activity counts/min | (18) |
| Time in light intensity (any min) | 100–573 Activity counts/min | (52) |
| Time in light intensity (any min) | 100–759 Activity counts/min | (33) |
| Time in light intensity (any min) | 100–1,951 Activity counts/min | (10,11,15,23,49) |
| Time in light intensity (any min) | 260–1,951 Activity counts/min | (37,40) |
| Time in light intensity (any min) | 100–2,019 activity counts/min | (52) |
| Time in light intensity (any min) | 500–2,019 Activity counts/min | (12,13,17) |
| Proportion of time in light intensity | Proportion of valid wear time at 100–759 activity counts/min | (33) |
| Steps in light intensity (any min) | Steps detected in 500–2,019 activity counts/min | (12) |
| Time in moderate-intensity activity (any min) | 574–4,944 Activity counts/min | (52) |
| Time in moderate-intensity activity (any min) | 2,020–5,998 Activity counts/min | (2,6,16,17,27,30,35,38,52) |
| Steps in moderate-intensity activity (any min) | Steps detected in 2,020–5,998 activity counts/min | (12) |
| Time in moderate intensity (modified 10-min bouts) | ≥500 Activity counts/min | (21) |
| Time in moderate intensity (modified 10-min bouts) | 760–5,999 Activity counts/min | (44) |
| Time in moderate intensity (modified 10-min bouts) | ≥1,000 Activity counts/min | (21) |
| Time in moderate intensity (modified 10-min bouts) | ≥1,500 Activity counts/min | (21) |
| Time in moderate intensity (modified 10-min bouts) | ≥2,000 Activity counts/min | (21) |
| Time in moderate intensity (≥10-min bouts) | ≥2020 Activity counts/min | (53) |
| Time in moderate intensity (modified 10-min bouts) | 2,020–5,998 Activity counts/min | (2,13,28) |
| Time in vigorous-intensity activity (any min) | ≥4,945 Activity counts/min | (52) |
| Time in vigorous-intensity activity (any min) | ≥5,999 Activity counts/min | (2,7,12,13,16,17,27,30,32,35,38,52) |
| Time in vigorous (any min) | Not reported | (6) |
| Steps in vigorous-intensity activity (any min) | Steps detected ≥5,999 activity counts/min | (12) |
| Time in vigorous intensity (modified 10-min bouts) | ≥5,999 Activity counts/min | (2,28,32,44) |
| Time in MVPA (any min) | ≥500 Activity counts/min | (21) |
| Time in MVPA (any min) | ≥574 Activity counts/min | (52) |
| Time in MVPA (any min) | ≥760 Activity counts/min | (37) |
| Time in MVPA (any min) | ≥1,000 Activity counts/min | (21) |
| Time in MVPA (any min) | ≥1,500 Activity counts/min | (21) |
| Time in MVPA (any min) | ≥1,952 Activity counts/min | (10,11,19,22,23,37,40) |
| Time in MVPA (any min) | ≥2,000 Activity counts/min | (21) |
| Time in MVPA (any min) | ≥2,020 Activity counts/min | (2,7,18,33,41,43,50-52) |
| Proportion of time in MVPA | Proportion of valid wear time ≥2,020 activity counts/min | (18,33) |
| Time in MVPA (any min outside a ≥10-min bout) | ≥760 Activity counts/min | (36) |
| Time in MVPA (modified 10-min bouts) | ≥2,020 Activity counts/min | (1,6,18,28,38,46) |
| Time in MVPA (in bouts ≥10 min) | ≥760 Activity counts/min | (36) |
| Time in MVPA (in bouts ≥10 min) | ≥2,020 Activity counts/min | (35) |
| Time active | >100 Activity counts/min | (29) |
| Time in total PA | ≥260 Activity counts/min | (40) |
| Day/wk ≥MVPA | ≥2,020 Activity counts/min | (6) |
| Adherence to PA recommendations (modified 10-min bout) | 30 Min of moderate or greater intensity activity on 5 of 7 d | (2,13) |
| Uncensored (raw) steps/d | Reporting steps as detected | (9,12,13,20,28,51,53) |
| Censored steps/d | Disqualify steps taken at less than 500 activity counts/min | (9,12,13) |
| Uncensored (raw) steps/min | Total raw steps accumulated during 1,440 min (24 h or 1 d), divided by time worn | (13) |
| Censored steps/min | Total steps accumulated during 1,440 min after censoring out steps at an intensity <500 activity counts/min, divided by time worn | (13) |
| Transitions/d | Total occurrences of when activity counts rose from <100 activity/counts in 1 min to ≥100 activity counts in the subsequent min | (13,15,29) |
| Basal physical activity | <2,500 Steps/d | (5,12,13) |
| Limited physical activity | 2,500–4,999 Steps/d | (5,12,13) |
| Sedentary | <5,000 Steps/d | (9,28) |
| Low active | 5,000–7,499 Steps/d | (5,12,13,28) |
| Low- to somewhat active | 5,000–9,999 Steps/d | (9) |
| Somewhat active | 7,500–9,999 Steps/d | (5,12,13,28) |
| Active to highly active | ≥10,000 Steps/d | (9) |
| Active | 10,000–12,499 Steps/d | (5,12,13) |
| Active | ≥10,000 Steps/d | (28) |
| Highly active | ≥12,500 Steps/d | (5,12,13) |
| Time in incremental cadence bands | 0 Steps/min (nonmovement) | (20) |
| 1–19 Steps/min (incidental movement) | ||
| 20–39 Steps/min (sporadic movement) | ||
| 40–59 Steps/min (purposeful steps) | ||
| 60–79 Steps/min (slow walking) | ||
| 80–99 Steps/min (medium walking) | ||
| 100–119 Steps/min (brisk walking) | ||
| ≥120 Steps/min (all faster human locomotor movements) | ||
| Peak 1-min cadence | Steps/min recorded for the single highest min in a day | (5) |
| Peak 30-min cadence | Average steps/min recorded for the 30 highest, but not necessarily consecutive, min in a day | (5) |
Abbreviation: MVPA, moderate- to vigorous-intensity physical activity.
a Hagströmer et al (43) also reported the number of bouts and accumulated time in each bout in each intensity category (sedentary, low, lifestyle, and moderate or greater). A sedentary bout was defined as more than 5 consecutive minutes within the designated count range, including an allowance for 1 minute above threshold (29). An MVPA bout was defined as 10 or more consecutive minutes within the designated count range, including an allowance for interruption of 1 or 2 minutes below threshold. Metzger et al (38) considered 70% of minutes above threshold in a 10-minute bout; all others considered 80%.