Table 1. Baseline Participant Characteristics by Group.
| Variable | Study Group, No (%)a | ||
|---|---|---|---|
| All (N = 258) | Incentive (n = 128) | Active Control (n = 130) | |
| Age, mean (SD), y | 48.0 (10.5) | 46.9 (10.2) | 49.2 (10.6) |
| Sex | |||
| Male | 33 (12.8) | 16 (12.5) | 17 (13.1) |
| Female | 225 (87.2) | 112 (87.5) | 113 (86.9) |
| Self-reported race | |||
| White | 235 (91.1) | 115 (89.8) | 120 (92.3) |
| Black | 12 (4.7) | 8 (6.3) | 4 (3.1) |
| Other | 11 (4.3) | 5 (3.9) | 6 (4.6) |
| Self-reported ethnicity | |||
| Hispanic or Latino | 15 (5.8) | 6 (4.7) | 9 (6.9) |
| Non-Hispanic or non-Latino | 243 (94.2) | 122 (95.3) | 121 (93.1) |
| Educational level | |||
| High school or less | 33 (12.8) | 11 (8.6) | 22 (16.9) |
| Some college | 76 (29.5) | 34 (26.6) | 42 (32.3) |
| College degree | 74 (28.7) | 41 (32.0) | 33 (25.4) |
| Postgraduate | 75 (29.1) | 42 (32.8) | 33 (25.4) |
| Annual income | |||
| <$50 000 | 29 (11.2) | 14 (10.9) | 15 (11.5) |
| $50 000-$99 999 | 127 (49.2) | 65 (50.8) | 62 (47.7) |
| $100 000-$149 999 | 76 (29.5) | 35 (27.3) | 41 (31.5) |
| ≥$150 000 | 26 (10.1) | 14 (10.9) | 12 (9.2) |
| Willing to give up something today to benefit in the future | |||
| Most averse to risks | 9 (3.5) | 3 (2.3) | 6 (4.6) |
| Moderately averse to risks | 183 (70.9) | 87 (68.0) | 96 (73.8) |
| Least averse to risks | 66 (25.6) | 38 (29.7) | 28 (21.5) |
| Postpone things although it would be better to get done right away | |||
| Most averse to risks | 89 (34.5) | 45 (35.2) | 44 (33.8) |
| Moderately averse to risks | 135 (52.3) | 65 (50.8) | 70 (53.8) |
| Least averse to risks | 34 (13.2) | 18 (14.1) | 16 (12.3) |
| Baseline IPAQ level | |||
| Low | 48 (18.6) | 28 (21.9) | 20 (15.4) |
| Moderate | 107 (41.5) | 55 (43.0) | 52 (40.0) |
| High | 102 (39.5) | 44 (34.4) | 58 (44.6) |
| Missingb | 1 (0.4) | 1 (0.8) | 0 |
| Household size, mean (SD), No. of persons | 3.0 (1.4) | 3.2 (1.6) | 2.8 (1.3) |
| BMI at randomization, mean (SD) | 32.1 (3.9) | 32.6 (4.2) | 31.7 (3.7) |
| Weight loss before randomization, mean (SD), kg | 11.6 (4.2) | 11.8 (4.1) | 11.5 (4.3) |
| Activity by IPAQ, median (IQR), min/wkb,c | |||
| Moderate to vigorous | 150.0 (40.0-305.0) | 145.0 (50.0-270.0) | 180.0 (30.0-390.0) |
| Walking | 210.0 (100.0-420.0) | 210.0 (105.0-420.0) | 210.0 (100.0-480.0) |
| Total MET | 1853.0 (982.5-3582.0) | 1653.0 (982.5-2940.0) | 2044.5 (918.0-4158.0) |
| Domain of eating behavior, mean (SD) scored | |||
| Cognitive restraint | 63.7 (14.3) | 64.1 (15.6) | 63.2 (12.9) |
| Uncontrolled eating | 42.2 (17.9) | 42.7 (17.9) | 41.8 (17.9) |
| Emotional eating | 52.6 (24.9) | 53.9 (24.5) | 51.4 (25.4) |
Abbreviations: BMI, body mass index (calculated as weight in kilograms divided by height in meters squared); IPAQ, International Physical Activity Questionnaire; IQR, interquartile range; MET, metabolic equivalent of task.
a
Percentages have been rounded and may not total 100.
b
One participant from the incentive group had physical activity data at baseline excluded because it was considered an outlier by the IPAQ scoring protocol.
c
Measured at baseline.
d
Measured at baseline using the Three-Factor Eating Questionnaire–R18. Scores range from 18 to 76, with higher scores indicating higher cognitive restraint and emotional and uncontrolled eating.