Table II.
Univariate and multivariate estimated effects of covariates on the average daily steps (log transformed) and sedentary time (% of wear time)
| Average daily steps | Sedentary time | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Univariate findings | Multivariate findings | Univariate findings | Multivariate findings | ||||||||
| Factor | Level | Median (IQR) | Coefficient (95% CI) | p | Coefficient (95% CI) | p | Mean (SD) | Coefficient (95% CI) | p | Coefficient (95% CI) | p |
| Age (y) | <13 | 9489 (5850–12 840) | – | – | – | – | 49.0 (13.9) | – | – | – | – |
| 13–18 | 8017 (2001–10 594) | 0.614 (0.331–1.000) | 0.081 | 0.647 (0.388–1.081) | 0.095 | 64.3 (22.2) | 15.2 (4.3–26.1) | 0.007a | 14.1 (3.6–24.7) | 0.010a | |
| ≥19 | 3250 (1486–4809) | 0.323 (0.213–0.491) | <0.001a | 0.382 (0.260–0.562) | <0.001a | 74.4 (12.6) | 25.7 (17.4–34.0) | <0.001a | 22.6 (14.6–30.5) | <0.001a | |
| Walking ability | Assisted | 3000 (1336–4139) | – | – | – | – | 74.3 (15.5) | – | – | – | – |
| Independent | 7580 (3590–9585) | 2.485 (1.524–4.053) | <0.001a | 2.111 (1.419–3.143) | 0.001a | 59.5 (18.6) | –14.8 (–25.4 to –4.2) | 0.007a | –11.4 (–19.6 to –3.2) | 0.007a | |
| Scoliosis | No | 8053 (3494–12 819) | – | – | – | – | 56.6 (18.4) | – | – | – | – |
| Yes | 4959 (1680–7077) | 0.545 (0.354–0.840) | 0.007a | 0.848 (0.583–1.233) | 0.382 | 69.4 (17.5) | 12.7 (3.8–21.7) | 0.006a | 2.5 (–5.2 to 10.2) | 0.523 | |
| Epilepsy | Never or none in the last 2 years | 6539 (2658–10 762) | – | – | – | – | 57.6 (20.1) | – | – | – | – |
| Less than monthly or monthly | 5069 (2671–9215) | 0.830 (0.494–1.395) | 0.476 | 1.062 (0.701–1.611) | 0.770 | 63.2 (16.6) | 5.6 (–5.0 to 16.3) | 0.295 | –0.3 (–8.8 to 8.3) | 0.948 | |
| Weekly or daily | 2642 (1636–5118) | 0.456 (0.262–0.794) | 0.006a | 0.633 (0.406–0.986) | 0.044 | 75.5 (12.4) | 17.9 (6.6–29.3) | 0.003a | 11.1 (2.0–20.3) | 0.018a | |
Coefficient values for average daily steps represent the ratio of the expected geometric mean for each category in relation to the baseline category.
a
p<0.05. IQR, interquartile range; CI, confidence interval.