Table 2.
Minimum number of days required to estimate weekly level of daily step count with ICC ≥ 80% and the corresponding MAPE (N = 212,048).
| Characteristics | Simple random days | Random consecutive days | ||
|---|---|---|---|---|
| Minimum number of days | MAPE (%) | Minimum number of days | MAPE (%) | |
| Total | 2.5 (0.5) | 14.6 (2.4) | 2.7 (0.5) | 14.5 (1.9) |
| Nationality | p-value = 0.157 | p-value = 0.083 | ||
| Singaporean | 2.5 (0.5) | 14.3 (2.4) | 2.7 (0.5) | 14.1 (1.8) |
| Foreigner | 2.6 (0.5) | 14.9 (2.4) | 2.9 (0.4) | 14.6 (1.7) |
| Gender | p-value = 1.000 | p-value = 0.046 | ||
| Female | 2.5 (0.5) | 14.9 (2.5) | 2.7 (0.5) | 14.9 (1.9) |
| Male | 2.5 (0.5) | 14.3 (2.3) | 2.9 (0.4) | 13.5 (1.5) |
| Age (years) | p-value < 0.001 | p-value < 0.001 | ||
| 17–39 | 3.0 (< 0.1) | 13.7 (0.7) | 3.0 (< 0.1) | 14.7 (0.9) |
| 40–59 | 2.5 (0.5) | 14.2 (2.4) | 2.6 (0.5) | 14.4 (2.0) |
| 60–79 | 2.0 (< 0.1) | 13.7 (0.8) | 2.1 (0.3) | 13.9 (1.0) |
| 80 + | 2.0 (< 0.1) | 12.4 (0.9) | 2.0 (0.2) | 12.7 (1.1) |
| Body mass index (kg/m2) | p-value = 0.008 | p-value < 0.001 | ||
| < 18.5 | 2.3 (0.5) | 15.9 (2.3) | 2.6 (0.5) | 15.5 (2.1) |
| 18.5 to < 23 | 2.5 (0.5) | 14.4 (2.2) | 2.8 (0.4) | 14.2 (1.7) |
| 23 to < 27.5 | 2.5 (0.5) | 14.4 (2.3) | 2.7 (0.5) | 14.2 (1.8) |
| ≥ 27.5 | 2.6 (0.5) | 14.6 (2.3) | 3.0 (< 0.1) | 13.7 (0.8) |
| Participation of previous program season | p-value = 0.317 | p-value = 0.317 | ||
| No | 2.5 (0.5) | 15.0 (2.2) | 2.7 (0.5) | 14.8 (1.7) |
| Yes | 2.5 (0.5) | 14.1 (2.3) | 2.8 (0.4) | 13.9 (1.7) |
| Step tracking device | p-value < 0.001 | p-value < 0.001 | ||
| HPB tracker 1 | 2.3 (0.5) | 14.0 (1.8) | 2.5 (0.5) | 13.5 (1.7) |
| HPB tracker 2 | 2.0 (< 0.1) | 13.1 (0.9) | 2.0 (< 0.1) | 13.7 (1.0) |
| HPB tracker 3 | 2.6 (0.5) | 8.6 (2.2) | 2.7 (0.5) | 8.8 (2.2) |
| HPB tracker 4 | 2.6 (0.5) | 10.4 (1.9) | 2.8 (0.4) | 10.3 (1.5) |
| iPhone | 3.0 (0.2) | 15.0 (1.1) | 3.5 (0.5) | 14.2 (1.9) |
| Samsung phone | 3.0 (< 0.1) | 14.7 (0.8) | 3.5 (0.5) | 14.0 (2.0) |
| Fitbit | 3.0 (< 0.1) | 11.3 (0.4) | 3.0 (0.0) | 12.1 (0.6) |
| Actxa | 2.4 (0.5) | 13.1 (2.0) | 2.5 (0.5) | 13.1 (2.2) |
Data are in mean (SD) of results over 22 separate weeks. p-values were from Friedman's tests to compare minimum number of days required between participant groups (Supplementary Table S1).
ICC intraclass correlation coefficients, MAPE mean absolute percentage errors, HPB Health Promotion Board.