Table 1.
Differences in intervention components between treatment arms.
| Intervention component | Sima | Seqb | App-Only arm | Theoretical construct | Behavior change technique [5] |
| Weight loss goal: 0.5-2.0 lb/week (tailored) and 5% by 12 weeks | ✓c | ✓ | ✓ | Self-regulation | Goal setting (outcome) |
| Calorie goal: tailored based on individual factors and rate of weight loss; minimum 1200 kcal for women, 1500 kcal for men | ✓ | ✓ (delayed) | ✓ | Self-regulation | Goal setting (behavior) |
| Self-monitoring of body weight: daily via the app | ✓ | ✓ | —d | Self-regulation | Prompt self-monitoring of behavioral outcome |
| Self-monitoring of dietary intake: daily via the app | ✓ | ✓ (delayed) | ✓ | Self-regulation | Prompt self-monitoring of behavior |
| Facilitate mastery experience by first tracking weight then tracking diet | — | ✓ | — | Self-efficacy; self-regulation; mastery | Set graded tasks |
| In-app real-time feedback | ✓ | ✓ | ✓ | Self-regulation; self-efficacy | Provide feedback on performance |
| Out-of-app summary feedback via weekly email (tailored) | ✓ | ✓ | — | Self-regulation; self-efficacy | Provide feedback on performance; prompt review of outcome goals; prompt review of behavioral goals |
| Skills training via weekly email with structured behavioral lesson and tips on how to use features of the app | ✓ | ✓ | — | Outcome expectancies; self-efficacy | Provide information on consequences of behavior in general; prompt generalization of a target behavior; provide information on when and where to perform the behavior; provide instruction on how to perform the behavior; environmental restructuring; plan social support/social change; relapse prevention/coping planning |
| Action plans via weekly email | ✓ | ✓ | — | Self-regulation; self-efficacy | Action planning; motivational interviewing [33]; barrier identification/problem solving [34]; prompt practice; plan social support/social change |
| Reminder of goals | ✓ | ✓ | — | Self-regulation | Prompt review of outcome goals; prompt review of behavioral goals |
| In-app automated reminders to track diet and/or weight sent daily (App-Only received reminders to track diet, Simultaneous received both diet and weight tracking reminders, and Sequential received weight tracking for all 12 weeks and diet tracking reminders starting in week 5) | ✓ | ✓ | ✓ | Self-regulation | Teach to use prompts/cues |
aSim: Simultaneous self-monitoring intervention arm.
bSeq: Sequential self-monitoring intervention arm.
cThe component is present.
dThe component is not present.