Table 2.
Comparisons | Fitbit plus motivational interviewing and habit education | Fitbit alone | Between-groups effect size for change (Cohen d) | ||||||
Baseline, mean (SD) | 12 weeks, mean (SD) | Changea (post-pre), mean (SD) | Within-group effect size (Cohen d) | Baseline, mean (SD) | 12 weeks, mean (SD) | Changea (post-pre), mean (SD) | Within-group effect size (Cohen d) | ||
Average steps/day (n=91) | 7496.88 (2895.94) | 7574.38 (3499.38) | 77.50 (2293.78) | .02 | 7519.60 (2259.13) | 7221.80 (2106.18) | –297.80 (2658.84) | 0.14 | 0.15 |
Average minutes of MVPAb/day (n=81) | 68.57 (3.93) | 68.91 (31.51) | .35 (3.96) | .13 | 75.06 (23.41) | 69.93 (21.74) | –5.12 (24.40) | 0.06 | 0.20 |
Average minutes of MVPA in 10+ min bouts/week (n=81) | 77.99 (118.83) | 93.16 (122.95) | 15.17 (122.86) | .13 | 86.19 (78.99) | 81.13 (77.55) | –5.07 (87.51) | 0.17 | 0.19 |
Average minutes of sedentary time/day (n=91) | 550.69 (102.74) | 563.81 (106.53) | 13.11 (99.68) | .14 | 547.96 (106.52) | 529.94 (111.61) | –18.02 (112.82) | 0.04 | 0.29 |
Average minutes of sedentary time in 30+ min bouts (n=91) | 290.63 (128.34) | 308.63 (127.37) | 18.00 (88.41) | .01 | 279.35 (117.62) | 284.22 (103.72) | 4.87 (115.27) | 0.23 | 0.13 |
aPositive values for change scores indicate an increase from pre- to postintervention.
bMVPA: moderate-to-vigorous intensity physical activity.