Table 2.
Intervention characteristics.
| Author(s)(year) | Intervention name | Intervention duration | Intervention type | Primary mode(s) of delivery | Level of support | Theoretical basis | Message content and frequency |
|---|---|---|---|---|---|---|---|
| Aguiar et al.(2016) | PULSE | 6 months | Independent | Website and DVD | Stand alone | Social Cognitive Theory | The PULSE Program was entirely self-paced and included the (also self-paced) Self-Help, Exercise and Diet Using Internet Technology (SHED-IT) weight loss program for men. |
| Arens et al. (2018) | NA | 12 months | Independent | Smartphone application | Remote and face-to-face support via physician | NR | Participants were to regularly enter weight, abdominal girth, blood pressure, and blood glucose into the app. Participants were invited to attend up to nine classes on nutrition and physical activity. Via a web-portal, physicians provided participants with regular feedback, messages, and goal modification. |
| Block et al.(2015) | Alive-PD | 6 months | Independent | Website, Interactive Voice Response, and Email | Stand alone | Learning Theory; Social Cognitive Theory; Theory of Planned Behaviour | The Alive-PD was self-administered. Two weekly health notes provided health information. Participants engaged in weekly tailored goal setting and tracking. Individually tailored print materials were sent monthly. Automated individually tailored phone coaching was delivered every two weeks via Interactive Voice Response. |
| Castro Sweet et al. (2018) | Omada Health Program | 12 months (16 week intensive + 36 week maintenance) | Diabetes Prevention Program | Website and smartphone application | Online support via health coach | Social Cognitive Theory; Transtheoretical model | For the initial 16-week intensive weight loss phase, participants completed one 1-hour online lesson each week. Less frequent lessons were completed in the subsequent 36-week weight maintenance phase. Participants engaged with their health coach and other participants online throughout the 12-month program. |
| Cha et al.(2014) | NA | 12 weeks | Independent | Website and smartphone application | Remote phone support via undergraduate student | Social Cognitive Theory; AADE7 Self-Care Behaviors Framework | Participants submitted weekly dietary and exercise habits and biweekly assignments. An undergraduate student on the research team provided weekly script-based phone counselling sessions. |
| Estabrooks and Smith-Ray(2008) | NA | 3 months | Independent | Interactive Voice Response | Stand alone | NR | Automated calls delivered once per week for 12 weeks. Seven calls provided 5–10 minutes of counselling and the remaining five calls provided a tip of the week. |
| Everett et al. (2018) | Sweetch Mobile Intervention | 3 months | Independent | Smartphone application | Stand alone | Just-in-time adaptive intervention design | The Sweetch app used machine learning to present users with content based on their own real-world life habits. Message content and frequency varied between users. |
| Fischer et al. (2016) | NA | 12 months | Diabetes Prevention Program | Short Message Service (SMS) | Face-to-face and phone support via health coach, and nutritionist or nurse. | Social Cognitive Theory; Transtheoretical model | Participants received six text messages per week and were prompted to report their weight once per week. Participants were eligible for motivational interviewing phone appointments with a health coach, in addition to weight loss resources such as access to DPP classes and appointments with a nutritionist or nurse for diet support. |
| Fukuoka et al.(2015) | mDPP | 5 months | Diabetes Prevention Program | Smartphone application | Face-to-face support via non-medical research staff | Social Cognitive Theory; Transtheoretical model | The mobile app delivered daily messages, video clips, and quizzes. Participants attended six in-person sessions within a 4-month period. |
| Kramer et al. (2010) | GLB-DVD | 3 months | Group Lifestyle Balance | DVD | Remote phone support via health care professional | Social Cognitive Theory; Transtheoretical model | Participants viewed one DVD per week. Participants contacted by health care professional once per week to review performance and voice questions/concerns. |
| Limaye et al. (2017) | LIMIT (Lifestyle modification in IT) | 12 months | Independent | Short Message Service (SMS) and Email | Stand alone | NR | Participants received lifestyle modification information via mobile phone and e-mail for one year. Three mobile phone messages and two e-mails were sent per week. A total of 150 phone messages and 100 emails were sent to each participant during the intervention period. |
| Ma et al. (2013) | E-LITE | 15 months (3 month intensive + 12 month maintenance) | Group Lifestyle Balance | DVD | Stand Alone | Social Cognitive Theory; Transtheoretical model | In the intensive treatment phase, participants were instructed to watch one DVD session per week for 12 weeks. In the maintenance phase, participants received an email reminder every two weeks to continue self-monitoring. |
| Michaelides et al. (2016) | Noom Coach | 24 weeks (16 week core + 8 week post-core) | Diabetes Prevention Program | Smartphone application | Remote app-based support via health coach | Social Cognitive Theory; Transtheoretical model | Participants received daily articles and interactive challenges and log their weight, meals, and physical activity each week into the app. The health coach communicated with participants twice per month. |
| Piatt et al.(2013) | GLB-DVD | 12–14 weeks | Group Lifestyle Balance | DVD | Phone support via registered nurse or dietician | Social Cognitive Theory; Transtheoretical model | Participants instructed to watch one DVD session per week for 12 weeks. Participants also met as a group at four time points within the 12-week period. Preventionists and lay health coaches called participants weekly to offer information and support. |
| Piatt et al.(2013) | GLB-Internet | 12–14 weeks | Group Lifestyle Balance | Website | Online counselling via registered nurse or dietician | Social Cognitive Theory; Transtheoretical model | Participants were instructed to watch one video per week for 12 weeks. Participants also met as a group at baseline and again after completing the intervention. Preventionists and lay health coaches supported participants via online counselling. |
| Ramachandran et al. (2013) | NA | 24 months | Independent | Short Message Service (SMS) | Stand alone | Transtheoretical Model | Participants received 2–4 text messages per week for 24 months. Messages contained <160 characters. |
| Sepah et al. (2014) | Prevent (Omada Health Program) | 12 months (16 week core + 36 week post-core) | Diabetes Prevention Program | Website and smartphone application | Online support via health coach | Social Cognitive Theory; Transtheoretical model | Participants were matched into online groups of 10 to 15 people and communicated via online social network. In the 16-week core phase, participants completed 16 weekly online lessons. In the 12-month post-core phase, participants completed 9 monthly lessons. |
| Tate et al.(2003) | Basic Internet | 12 months | Independent | Website | Stand alone | NR | Weekly weight loss tutorials and tips were delivered via website. Participants were sent weekly email reminders to submit weight. |
| Tate et al.(2003) | Internet and Behavioral e-Counseling | 12 months | Independent | Website and Email | Remote e-mail support via counsellor | NR | Weekly weight-loss tutorials and tips were delivered via website. Participants were sent weekly email reminders to submit weight. The counsellor emailed participants five times during the first month and weekly for the remaining 11 months. |
| Wilson et al.(2017) | Omada Health Program | 12 months (16 week core + 36 week post-core) | Diabetes Prevention Program | Website and smartphone application | Online support via health coach | Social Cognitive Theory; Transtheoretical model | For the initial 16-week intensive weight loss phase, participants completed one lesson each week. Participants completed additional weekly lessons during the subsequent 36-week weight maintenance phase. Participants engaged with their health coach and other participants online throughout the 12-month program. |
| Wong et al. (2013) | NA | 24 months | Independent | Short Message Service (SMS) | Stand alone | Social Cognitive Theory; Theory of Planned Behaviour | Phase 1: three text messages per week (36 total)Phase 2: one text per week (12 total)Phase 3: one text per month (6 total)Phase 4: one text per month (12 total) |
Note: NA: not applicable; NR: not reported.