Descriptive statistics of the accelerometer data at baseline
| Mean | SD | Median (95% CI) | Range | 90th centile* | 75th centile* | 50th centile* | |
|---|---|---|---|---|---|---|---|
| Number of days wearing an accelerometer | 6.1 | 1.2 | 7 (6 to 7) | 3–7 | |||
| Mean wear time per day (hr) | 14.0 | 0.8 | 14.0 (13.9 to 14.2) | 11.3–16.0 | |||
| Overall physical activity, mean cpm/100 | 6.1 | 3.0 | 5.5 (4.9 to 6.1) | 2.4–29.2 | |||
| Per cent of the day spent at different levels of physical activity | |||||||
| Sedentary (0–100 cpm) | 66.1 | 6.0 | 65.8 (64.7 to 67.9) | 48.7–77.6 | 74.3 | 70.8 | 65.9 |
| Light (101–2295 cpm) | 26.1 | 4.0 | 25.7 (25.1 to 26.7) | 17.4–36.3 | |||
| Moderate (2296–4011 cpm) | 4.6 | 1.6 | 4.5 (4.0 to 5.0) | 1.7–10.1 | 11.9† | 9.9† | 7.2† |
| Vigorous (4012–50 000 cpm) | 3.2 | 2.2 | 2.7 (2.5 to 3.0) | 0.5–18.8 | 5.7 | 4.3 | 2.7 |
| Mean cpm for the time of the day spent in | |||||||
| Sedentary and light physical activity | 222 | 46 | 222 (208 to 229) | 130–385 | |||
| Sedentary, light and moderate physical activity | 356 | 87 | 353 (334 to 375) | 185–641 | |||
| Light, moderate and vigorous physical activity | 1747 | 678 | 1611 (1535 to 1676) | 1017–6442 | |||
*The proportion of the day spent at different levels of physical activity was dichotomised at these percentiles in the analyses.
†Presented for moderate and vigorous physical activity combined.
Cpm, counts per minute.