Table 2.
Baseline and 16-Week Follow-up Means and Effect Sizes for Outcomes
| Outcome |
Reliabilitya |
Baseline M (SD) |
16-Week Follow-up M (SD) |
Effect Size (95% CI)b |
|---|---|---|---|---|
| Medical record weight (lb)c | n/a | 214.9 (44.3) | 213.7 (43.1) | −0.03 ( −0.13, 0.07) |
| Self-reported weight (lb) | n/a | 206.3 (35.7) | 208.3 (44.3) | 0.06 (−0.04, 0.16) |
| Daily nutrientsd | n/a | |||
| Protein intake (g/day) | 71.5 (26.2) | 71.6 (22.8) | 0.00 (−0.40, 0.40) | |
| Carbohydrate intake (g/day) | 144.4 (74.3) | 141.6 (67.2) | −0.07 (−0.51, 0.37) | |
| Dietary fiber intake (g/day) | 4.3 (3.6) | 3.2 (4.7) | −0.28 (−0.81, 0.24) | |
| Total fat intake (g/day) | 62.8 (31.7) | 74.6 (48.3) | 0.30 (−0.25, 0.85) | |
| Physical activity (metabolic minutes/week)e | n/a | |||
| Walking | 821.4 (965.5) | 1271.7 (1221.0) | 0.38 (0.07, 0.69) | |
| Moderate intensity physical activity | 342.7 (450.0) | 893.4 (1371.3) | 0.52 (0.06, 0.97) | |
| Vigorous intensity physical activity | 1124.0 (1445.2) | 1424.3 (1636.9) | 0.23 (−0.25, 0.72) | |
| Total physical activity | 2288.0 (1942.7) | 3589.4 (3237.8) | 0.49 (0.11, 0.86) | |
| Recovery self-efficacy | ||||
| Diet | .68 | 3.3 (0.6) | 3.4 (0.6) | 0.25 (−0.36, 0.85) |
| Physical activity | .73 | 3.3 (0.5) | 3.3 (0.7) | 0.10 (−0.36, 0.57) |
| Maintenance self-efficacy | ||||
| Diet | .93 | 3.3 (0.5) | 3.4 (0.5) | 0.26 (−0.13, 0.65) |
| Physical activity | .93 | 3.3 (0.6) | 3.4 (0.5) | 0.25 (−0.10, 0.60) |
| Satisfaction with outcomes | .92 | 2.5 (1.5) | 2.6 (1.3) | 0.22 (−0.02, 0.46) |
| Social supportf | ||||
| Family support-diet | .83 | 3.1 (1.1) | 3.6 (1.0) | 0.53 (0.22, 0.84) |
| Family sabotage-diet | .49 | 2.1 (0.8) | 2.0 (0.9) | −0.18 (−0.69, 0.32) |
| Family support- physical activity | .72 | 2.7 (0.8) | 3.0 (0.9) | 0.46 (0.13, 0.78) |
| Family sabotage- physical activity | .38 | 2.0 (0.7) | 2.0 (0.7) | 0.06 (−0.38, 0.49) |
| Friend support-diet | .82 | 2.7 (1.0) | 2.9 (0.9) | 0.16 (−0.29, 0.62) |
| Friend sabotage-diet | .50 | 2.1 (0.8) | 2.3 (1.1) | 0.28 (−0.22, 0.78) |
| Friend support-physical activity | .89 | 2.5 (1.1) | 2.8 (1.0) | 0.24 (−0.16, 0.63) |
| Friend sabotage- physical activity | .52 | 1.8 (0.7) | 2.1 (0.7) | 0.38 (−0.23, 0.99) |
| Frequency of weight monitoring (n (%)) | n/a | |||
| Daily | 8 (26.7%) | 11 (39.3%) | -- | |
| Nearly every day | 9 (30.0%) | 3 (10.7%) | -- | |
| 3 or 4 times a week | 3 (10.0%) | 6 (21.4%) | -- | |
| Once or twice a week | 2 (6.7%) | 6 (21.4%) | -- | |
| 2 or 3 times a month | 5 (16.7%) | 1 (3.6%) | -- | |
| Once a month | 1 (3.3%) | 1 (3.6%) | -- | |
| Less than once a month | 2 (6.7%) | 0 (0.0)% | ||
Abbreviations: M=mean, SD=standard deviation, CI=confidence interval, n/a=not applicable
Note. N=30 participants completed the baseline survey and, of those, N=28 completed 16-week follow-up surveys. Outcome data on self-reported weight were missing at baseline (n=1). At 16 weeks, there were missing data (n=1) for each daily nutrient intake outcome.
Reliability was assessed with Cronbach’s alpha.
The SAS macro %effect_size for one group pretest-posttest design was used to calculate effect sizes and 95% confidence intervals (Kadel & Kip, 2012). Calculations were restricted to participants with both baseline and 16-week data and utilized standard deviations of raw scores (rather than standard deviations of change scores).
N=30 for baseline and 16-week electronic medical record (EMR) weight. Baseline EMR weight represents the mean of participants’ weights measured closest, but prior, to baseline. 16-week EMR weight represents the mean of participants’ weights measured closest to 16 weeks post-baseline.
Obtained via Food Processor Nutrition Analysis software.
Metabolic minutes per week estimated from the Short Form of the International Physical Activity Questionnaire-Short for Telephone (Lee et al., 2011).
N=29 (baseline) and N=25 (16-week follow-up) participants reported having family in which to confide. N=22 (baseline) and N=14 (16-week follow-up) participants reported having a friend in which to confide. There were additional baseline missing values (n=1) for each of the four friend social support subscales. Reported means and standard deviations for the social support measures are based on these reduced sample sizes.