Table 2 Study intervention characteristics.

Abbott et al., 2020 [42]

England

Prospective cross-sectional

Adults with a body mass index (BMI) ≥ 40 kg/m² or ≥35 kg/m² with comorbidities

N: 227

A: 44 ± 12 years

F: 160 (71)

M: /

White British (63)

Other (24)

Unknown (14)

Video-conference

INT: Tier 3 weight management programme. 6 ×1 h online video conference group sessions for 6 months

Recruitment rate of those eligible (n = 277/315; 72.1%). Patients who were older and/or from ethnically diverse backgrounds were more likely to decline. The most common reason was lack of internet access and/or lack of digital skills (89.8%, n = 79/88) with 10.2% (n = 9/88) who declined as they preferred face-to-face sessions.

Abshire et al., 2020 [43]

United States

Cross-sectional survey

Primary care patients with a BMI ≥ 30 kg

N = 77

A: 46 ± 13 years

F: 72 (94)

M: 5 (6)

African American (67)

White (22)

Mixed (7)

Other (4)

<High school (9)

High school (16)

College (36)

>degree (40)

n/a

n/a

Allen et al., 2013 [44]

United States

RCT

Individuals aged 21–65 years with a BMI of 28–42 kg/m² with access to a smartphone

N = 68

INT: (n = 16);

CON (1) (n = 18) CON (2) (n = 17)

CON (3) (n = 17).

A: 44.9 ± 11.1 years

F: 53 (78)

M: 15 (22)

African American (49)

College (67)

Fulltime employment (84)

mHealth App + in-person counselling

INT: Months 2–6: biweekly 1 x1 h counselling session for 6 months delivered by nutritionist coach. Weight loss mHealth app which provides real-time feedback, self-monitors food intake/activity, and tracks progress with weekly weigh-ins encouraged with opportunities for social networking and support.

COM: (1) intensive counselling (2) less intensive counselling + smartphone App

(3) Smartphone App only

Recruitment rate of those eligible (n = 68/110; 62%). Refusal is mostly related to inconvenience.

63% Follow-up (n = 43). Counselling sessions attended (M = 72%) days of diet smartphone entries (M = 53%); days of physical activity smartphone entries (M = 32%)

Arigo et al., 2015 [45]

United States

Feasibility study

Women aged ≥25 years engaging in less than 30 min of moderate-vigorous activity per week

N = 20

A: 50 ± 7.2 years

F: 20 (100)

M: n/a

White (95)

Degree (70)

Hybrid face-to-face/online delivery through social network

INT: 1×90-min face-to-face initial skills session delivered by the research team. Encouraged to contribute 1 post per week to the forum. Dashboard to check daily Physical activity totals, encouraged to sync devices & check progress at least twice per day. Intervention lasted 6 weeks.

Recruitment rate of those eligible (n = 20/31; 65%). 1 was injured, 6 had no response and 3 declined after receiving an overview of the study.

High retention (100%). High engagement with participants wearing trackers on 97% of days on average (range 80–100%).

Asbjornsen et al., 2020 [46]

Norway

Qualitative interviews and focus groups

Adults aged ≥18 years with a BMI ≥ 30 kg/m².

N = 23

A: 53 (24–70) years

F: 14 (67)

M: 9 (33)

/

n/a

n/a

Batsis et al., 2019 [47]

United States

Feasibility pre-post study

Adults aged ≥65 years with BMI ≥ 30 kg/m² who have access to high-speed internet.

N = 37

A: 69 ± 11.6 years

F: 32 (87)

M: /

White (100)

Video-conference

INT: 16 x weekly 1-1 sessions via video calls delivered by health coach, registered dietitian, & nurse exercise specialist.

Recruitment rate of those eligible (37/58; 64%). Reason for decline related to timing/logistical reasons (n = 11) and uninterest to participate in a video-delivered intervention (n = 10).

Retention was moderate 76% (27/37). Discontinuation was mostly related to noncompliance; one participant’s discontinuation was due to technology issues.

Approximately 93%, 96%, and 67% of participants attended greater than 75% of health coach, nurse, and dietitian sessions, respectively.

Batsis et al., 2020 [48]

United States

Qualitative interviews and focus groups

Adults aged ≥65 years who live in a rural location with a BMI ≥ 30 kg/m².

N = 29

A: 72.9 years

F: 16 (55)

M: /

/

Video-conference

INT: Weekly x 1-1 counselling sessions (15–20 min) delivered by a dietician, (Total = 26) and biweekly group exercise sessions (70–90 min) (Total = 13 sessions) delivered by an exercise instructor over 26 weeks.

COM: n/a

n/a

Batsis et al., 2021 [49]

United States

Feasibility pre-post study

Adults aged ≥65 years who live in a rural location with a BMI ≥ 30 kg/m².

N = 53

A: 72.9 ± 3.9 yrs

F: 37 (70)

M: /

High school (13.2)

College degree (28.3)

Post-college degree (30.2)

Video-conference

INT: 18 × 30 min1-1 live videoconference nutrition sessions delivered by registered dietician nurse + 7 1 x h group sessions (remote if necessary) + 75 min x 2 weekly synchronous videoconferencing group exercise sessions delivered by personal trainer (Total = 40 sessions). Every 3–4 weeks an additional on-site group session. Weekly food records reviewed, and attendance monitored. Activity tracker to self-monitor physical activity. Intervention lasted 26 weeks.

Recruitment rate of those eligible (53 /115; 46%). Reason for decline related to being uninterested in participating in a video-delivered intervention (n = 27) worry about technology (n = 5) and logistical/competing responsibilities (n = 30).

High retention was found for the intervention arm (44/53; 83.0%).

Attendance rates for video/on-site visits were 77% and 78.2% for exercise sessions and 84% and 90.0%, for dietician visits respectively. Participants wore wearable trackers for an average of 81.7% days with a mean time of 8.3 ± 3.8 h per day.

Bennett et al., 2018 [50]

United States

RCT

Filipino adults with a BMI of >23 kg/m² diagnosed with Type 2 Diabetes (non-insulin-dependent) and own a smartphone, tablet, or laptop computer

N = 351

INT (n = 176)

CON (n = 175)

A: 50.9 ± 9.1 years

F: 120 (68)

M: 112 (32)

Non-Hispanic black (52)

Non-Hispanic white (29)

Hispanic (13)

Other/missing (5)

>High school graduate (15)

High school graduate (36)

Some college (40)

>College degree (10)

Employed (67)

mHealth App and telephone calls

INT: The intervention included 1) tailored behavioural goals (e.g., walk 10,000 steps/day, no sugary drinks, no fast food); 2) self-monitoring of these goals via weekly interactive voice response phone calls/text messages; 3) daily self-weighing via a cellular-connected scale; 4) skills training materials in print and video; 5) 18 weight loss counselling coaching calls with a registered dietitian; and 6) brief weight loss counselling at medical visits. Intervention lasted 12 months.

COM: Usual Care

Recruitment rate not reported.

High retention in the intervention arm (96%) and usual care group (92%) at 12-month visits. 90% completed all three study visits.

Intervention participants completed a median of 93.2% and 89% of weekly self-monitoring and coaching calls respectively. Participants weighed for 42.9% of the expected days.

Cliffe et al., 2021 [51]

Wales

Qualitative interviews

Adults with a BMI of 35–45 kg/m² are referred by healthcare professionals to a dietetics service.

N = 13

A: 48.5 ± 20.2 years

F: 8 (62)

M: 5 (39)

White British (85)

White European (15)

Employed (54)

Retired (23)

Student (15)

Carer (8)

Video-conference

INT: Months 1–2: weekly group sessions; Months 4 + 6 group review sessions (Total = 10) delivered via a registered dietician. Written information and visual materials were sent via email a week before each session. Materials with hands-on activities. Intervention lasted 6 months.

COM: Usual Care

Recruitment rate of those eligible (14 /89; 17%). Reason for decline related to no response (42; 47%) and opting for face-to-face sessions (33; 37%).

Retention was moderate: 71% (10/14). Two withdrawals due to poor internet connection with one due to a medical condition.

n = 12 attended first session and n = 10 attended >5 sessions (83%).

Connelly et al., 2017 [52]

Scotland

Feasibility RCT

Adults with Type 2 Diabetes living in remote or rural locations

N = 31

Interactive web (n = 11)

Information web (n = 10);

CON (n = 10).

A: 67.3 ± 10.4 years

F: 13 (41)

M: 18 (59)

/

Interactive website

INT: Interactive web group with online access to diabetes-specific physical activity information and interactive features. Intervention lasted 6 months.

Recruitment rate of those eligible/interested in taking part (31/42; 74%).

Retention rate was high (90%).

<3 months participants logged an average of 12.5 (SD 15.7) times dropping to 11.3 (SD 37.1) times from 3- to 6-month follow-up. There was a large range in the number of logins per month (0–50). In the last 2 months, only 1 person continued to use the website.

Cook et al., 2019 [53]

Switzerland

Feasibility pre-post study

Adults aged 35 to 65 years with a BMI of 30–39 kg/m²

N = 23

A: 49.7 years

F: 16 (70)

M: 7 (30)

Caucasian (78)

Hispanic (17)

Mixed (4)

Interactive website

INT: Online Bulletin Board (OBB) website logins twice daily for at least 30 min for four consecutive days followed by 2 × 1.5 h telephone group discussions.

n/a

Damschroder et al., 2010 [54]

United States

Pilot feasibility pre-post study

Veterans that were eligible for the MOVE! Lifestyle programme.

N = 14

A: 53.8 ± 12.5 years

F: 5 (36)

M: 9 (64)

Minority ethnic groups (14)

Telephone calls

INT: Week 1 (1-1 face-to-face sessions); Weeks 2–5 (Weekly phone calls); Week 5 (onsite visit with a coach; Weeks 6–11 (weekly phone calls); Week 12 face to face. All sessions were delivered by a lifestyle coach. Activity tracker to self-monitor physical activity.

Recruitment rate (15/29; 52%). 11 declined to participate mostly related to not wanting to take part in a weight management study/preferring a group-based programme.

High retention (100%).

An average of 1.7 phone call attempts were made for each of the 146 completed coaching. The average duration of phone sessions was 32.4 (7.6) min. 92% of the 168 planned sessions (14 participants 12 sessions) were completed.

Das et al., 2014 [55]

Norway

Qualitative case study incorporating forum extracts and interviews

Adults with basic proficiency in Norwegian enrolled in a bariatric weight loss programme.

N = 60

A: 40 ± 9.3 years

F: 45 (75)

M: /

Primary school (7)

High school (53)

University/college (40)

Employed (66)

Student (5)

Unable to work/unemployed (27)

Online forum

INT: Online discussion forum and personal one-to-one communication (patient-to-patient and health care professional-to-patient or vice-versa). The moderator (researcher) posted weekly topics relevant to the patient group. 5 healthcare professionals N = 5) (1 x psychiatric nurse, 1x head nurse, 2 x nurses, 1 x dietician) had access to the eHealth portal and responded to any requests.

n/a

Das et al., 2017 [56]

United States

RCT

Adults already enrolled on a commercial weight loss programme.

N = 644

A: 18–39 (19), 40–59 (56), 60+ (25) years

F: 563 (87)

M: 81 (69

/

Video-conference

INT: 11 x weekly 1-h group meetings (either in community or worksite settings). Participants communicate with the group leader/other participants via a website message board and are encouraged to log weight.

COM: Same intervention but delivered in person

Recruitment rate not reported/unknown.

There were 71.6% complete reporters (461/644) defined as reporting at least one weight during the final week of their 11-week programme.

Videoconference participants, older adults, and enrollees in incentivised programmes were more likely to be a complete reporters.

Donnelly et al., 2007 [57]

United States

RCT

Adults with a BMI ≥ 30 kg/m² are otherwise judged as healthy and not using tobacco products.

N = 97

INT (n = 34)

clinic (n = 39)

CON (n = 24)

A: 53 ± 42 years

F: 51 (53)

M: 23 (24)

Missing: 23 (23)

/

Group phone call

INT: Weekly 60-min group phone calls with a health educator for 26 weeks.

COM: Face-to-face clinic

Recruitment rate not reported/unknown.

Retention at 12 weeks was moderate (74/97; 76%). Nine participants (26%) terminated/withdrew from the phone group, 12 from the clinic (31%), and two from control groups (9%). Reasons for attrition included not meeting the attendance requirement (scheduling conflicts), noncompliance with the study protocol, dissatisfaction with study conditions, and the participant’s perception they could continue successfully on their own.

Dutton et al., 2015 [58]

United States

Pilot feasibility

pre-post study

Adults with a BMI ≥ 30 kg/m² with ≥1 cardiometabolic risk factor/s.

N = 33

A: 56 ± 10.2 years

F: 29 (88)

M: 4 (12)

Black African American (85)

≤High school (42.4)

Hybrid face-to-face/telephone calls

INT: 12 × 60 min group-based office visits (with private weigh-ins) delivered by health professionals plus 12 individual phone contacts over 6 months (15 min) delivered by trained peer coaches.

Recruitment rate not reported/unknown.

High retention (85%). Participants attended approx. 50% of the group visits (6 ± 4 of 12 possible sessions) and completed approximately 40% of the intended telephone calls (i.e., 5 ± 3 of 12 scheduled calls). The mean duration of completed calls was 14 ± 7 min.

Gibson et al., 2020 [59]

United States

RCT with mixed methods evaluation

Adult kidney transplant recipients with a BMI > 22 kg/m² and the ability to report data with internet access.

N = 10

INT (n = 5)

CON (n = 5)

A: 45.2 ± 10.2 years

F: 5 (50)

M: 5 (50)

Non-Hispanic white (50)

Black African (20)

Mixed (20)

Hispanic (10)

High school (40)

Some college (40)

College graduate (20)

Video-conference

INT: 12 weeks of weekly 1-h group-based health coaching sessions delivered remotely by a registered dietitian and physical activity expert followed by 12 weeks of maintaining healthy behaviours.

Participants were encouraged to report healthy lifestyle behaviours weekly and to accumulate at least 150 min of moderate-intensity PA per week. Intervention lasted 6 months.

Recruitment rate of those eligible (10/10; 100%).

High retention: 9/10 (90%) with one voluntary withdrawal although not related to the intervention.

The attendance rate of health coaching sessions was 78% for the 12 sessions. Absences related to illness or schedule conflicts. Adherence to reporting healthy behaviours was 86% with technological issues cited as barriers to full reporting.

Goodrich et al., 2018 [60]

United States

Non-randomised trial with mixed methods evaluation

Veterans screened as having a BMI ≥ 25

N = 2818

INT (n = 530)

CON (n = 2282)

A: 57 ± 9.5 years

F: 75 (15)

M: 422 (85)

42 interviews with key stakeholders (dieticians, physicians, co-ordinators, champions)

White (80)

Black (16)

Other (3)

Telephone calls

INT: Participants receive an Interactive TeleMOVE messaging device alongside a Health Buddy, MOVE! handout booklet, a pedometer to track daily activity and a home-based digital scale. In the course of these interactive dialogues with the health buddy, patients entered weight information and any responses to daily prompts to be forwarded via landline phone each night to a vendor server which is forwarded to a co-ordinator. Participants also received 10- to 20-min telephone calls from a TeleMOVE coordinator every 30 days for any red alert questions.

Recruitment rate not reported/unknown.

High retention of 2 or more visits (6 months) in the intervention arm TeleMOVE (93.9%; 467/497) compared to the control arm MOVE! (71.97%; 1189/1652). Less engaged from non-white backgrounds in TeleMOVE (20%) compared to tMOVE! (35%). More people who live in a rural location engaged in TeleMOVE (57.9%) compared to MOVE! (41.93%).

Haggerty et al., 2016 [61]

United States

RCT/ Survey

Women with a BMI ≥ 30 kg/m² and endometrial hyperplasia or Type I endometrial cancer.

N = 20

Telemedicine (n = 10)

Texting (n = 10)

A: Median 63 years

F: 20 (100)

M: n/a

White (68)

Black (25)

Asian (4)

Other (3)

Telephone calls + text messages.

INT: 16 weekly telephone counselling sessions followed by bi-weekly sessions (weeks 18–24) delivered by two interventionists (master’s level clinician and medical doctor). Weight was recorded via a Wi-Fi scale shared via an internet platform with real-time feedback on participants’ progress.

Recruitment rate (60% of women approached expressed interest in participation; around 50% were eligible based on technology capabilities).

High retention. High retention (100%) and adherence (100%).

Harvey-Berino et al., 2002 [62]

United States

RCT

Adults with a BMI ≥ 25 kg/m² and access to a computer/internet.

N = 124

Internet support (n = 40)

Minimal in person support (n = 41)

Frequent in person support (n = 41)

A: Intervention only

46.3 ± 11.1 years

F: 36 (90) -

M: 4 (10)

White (98)

High school (10)

Some college (25)

College degree (28)

Graduate (38)

Email, video chat + discussion groups

INT: 1-h weekly sessions (N = 24) delivered by therapist for 24 weeks.

COM: (1) Frequent in-person support. (2) Minimal in-person support

Recruitment rate not reported/unknown.

Attrition was 18% after 6 months of treatment and 24% over 18 months of evaluation. A total retention rate of 73% for all data points.

Attendance was greater for face-to-face conditions than for the internet support condition.

Harvey-Berino et al., 2004 [63]

United States

RCT

Adults with a BMI ≥ 25 kg/m²) and access to a computer/internet.

N = 255

Internet (n = 77)

Minimal in person support (n = 78)

Frequent in person support (n = 77)

A: 45.8 ± 8.9 years

F: 209 (82)

M: 46 (18)

High school (9)

Some college (29)

College degree (29)

Graduate school (33)

Interactive television, email, + web chat

INT: 1-h weekly sessions (N = 24) delivered by local health educators, dietitians, site facilitators and a dietitian for 24 weeks.

COM: (1) Frequent in-person support

(2) Minimal in-person support

Recruitment rate not reported/unknown.

Retention was highest for the frequent in-person and minimal in-person with 88% (68/77) and 86% (67/78; 86%) compared to the internet support group (77%; 59/77) at 12 months.

Participants in the face-to-face condition attended significantly more group meetings than those in the internet support condition. Participants in the internet condition submitted self-monitoring diaries more frequently and reported significantly more peer support contacts than those in the face-to-face condition.

Harvey-Berino et al., 2010 [64]

United States

RCT

Adults with a BMI between 25 and 50 kg/m² and access to a computer/internet.

N = 481

Internet (n = 161) Hybrid (n = 162)

In person (n = 158)

A: 46.6 ± 9.9 years

F: 447 (93)

M: 34 (7)

African American (66)

College graduate (65)

Synchronous online chat

INT: 1-h weekly sessions (N = 24) delivered by graduate students, clinical psychologists, and registered dieticians for 24 weeks.

COM: (1) In-person

(2) Hybrid (Internet + in-person)

Invited/consent rate (658/1143; 56%). Declines mostly related to loss of interest (171;485; 35%) and no-show (293/485; 60.41%).

The Internet group had the highest retention rate (159/161; 99%) although retention was high across all groups (in person: 150/158; 95%, hybrid: 153/162; 94%). There were no significant differences in group sessions attended across conditions (76% Internet vs. 71% in-person vs. 72% Hybrid) or in the proportion of self-monitoring journals submitted.

Haste et al., 2017 [65]

England

RCT with mixed methods evaluation

Men with Type 2 diabetes and a BMI between 30–40 kg/m².

N = 61

INT (n = 33)

CON (n = 28)

A: 58 years

F: n/a

M: 61 (100)

White (100)

M = 12 years of education

Employed (83)

Retired (41)

Unemployed (15)

Unable to work (6)

Personalised web-based email-style consultations

INT: Dietician-based consultations: Months 1–3: weekly web-based sessions (Total = 12) Months 4–12 (monthly web-based sessions (Total = 9).

Exercise expert-based consultations: Months 1–3: Monthly web-based sessions (Total = 3), Months 4–12: Quarterly web-based sessions (Total = 3) delivered by dietitian and an exercise expert. Intervention lasted 12 months.

COM: Usual care

Invited/consent rate (61/968; 6.3%). This is mostly related to decline to participate (187/907; 21%) and non-response (696/907; 77%).

Retention was higher in the intervention group at 3 months (INT: 73%, CON: 57%) and at 12 months (INT: 61%, CON: 43%).

Logins to website at 12 months was a median of 43 (12–167), higher food intake entries with a median of 99 (3–246) compared to exercise entries 262 (0–262).

Hu et al., 2021 [66]

United States

RCT/ Survey

Adults (18–80 years) living with excess weight and prediabetic OR diagnosed with Type 2 diabetes.

N = 161

INT (n = 84)

CON (n = 77)

A: 58.6 ± 11.1 years

F: 107 (67)

M: 54 (34)

White (55)

Black African (25)

Other (19)

Missing (1)

High school (17)

Foundation degree (13)

>Bachelor’s degree (70)

Employed (72)

Video-conference

+ mHealth App

INT: Month 1: 1 x weekly sessions; Months 2–6: 1 x biweekly sessions (N = 14 sessions) delivered by the research team (dietitian, research associate). Intervention lasted 6 months.

Recruitment rate not reported/unknown.

Mean WebEx attendance = intervention 74.4% control 74.3%.

Days participants logged daily calorie goal in App (INT: 45.1; CON: 27.5). 84% completed post-study questionnaire (n = 100).

Job et al., 2017 [67]

Australia

RCT with mixed methods evaluation

Women (18–75 years) diagnosed with stage I–III breast cancer with BMI 25–40 kg/m²

N = 45

A: 56.0 ± 12.0

F: 45 (100)

M: n/a

White (96)

>High school (73)

Employed (62)

Phone calls + text messages

INT: 16 phone calls delivered by an accredited dietitian with an extended 6-month phase with tailored text messages delivered. Intervention lasted 12 months.

COM: Usual care

Recruitment rate in intervention of those eligible (30/40; 75%). Did not own a phone (n = 3), did not need support (n = 1), family/health reasons (n = 3), used phone for emergencies only (n = 1) with 2 not contactable.

More than half (57%, 17/30) of the women who participated in the extended contact intervention had received text messages during the initial 6-month intervention.

Kolodziejczyk et al., 2013 [68]

United States

Pre-post study

Adults (21–60 years) with a BMI of 27.0–39.9 and

willing/able to learn to text and can communicate in English/Spanish.

N = 20

A: 40.10 ± 8.05 years

F: 12 (60)

M: /

Hispanic (75)

White non-Hispanic (65)

Asian (10)

Missing (20)

College (40)

College graduate (15)

Graduate degree (35)

Missing (10)

Phone calls + text messages

INT: 3–5 x daily automatically scheduled and tailored text messages encouragement and reinforcement delivered by the research team. Intervention lasted 8 Weeks

Recruitment rate not reported/unknown.

High retention rate (90%; n = 18).

Participants responded to 88.04% (986/1120) of interactive text messages.

Latinen et al., 2010 [69]

Finland

Non-randomised trial with mixed methods evaluation

Adults at high risk of Type 2 Diabetes

N = 74

INT (n = 33)

CON (n = 41)

A: 49 years

F: 41 (55)

M:33 (65)

/

Video-conference

INT: 90-min group sessions at 2-week intervals with session 5 at 6 months delivered by a clinical nutritionist. Intervention lasted 6 months.

COM: The same intervention delivered face-to-face

Recruitment rate not reported/unknown.

High retention (73/74; 99%).

Lewis et al., 2021 [70]

Australia

Qualitative Focus groups

Participants who completed a previous telehealth trial

N = 15

A: 55 ± 12.0 years

F: 12 (80)

M: 3 (20)

/

Video-conference

+ text message

INT: 3 texts + 1 phone call per week x 4 months delivered by an accredited practising dietitian and exercise physiologist specialising in obesity. Intervention lasted 4 months.

n/a

May et al., 2019 [71]

United States

Cross-sectional survey

Female cancer survivors who completed active cancer treatment and are living with excess weight.

N = 96

A: 54.3 ± 9.6 years

F: 96 (100)

White (89)

Black (4)

Asian (3)

Hispanic (4)

Native American (1)

Grades 0–12 (2)

College (26)

College graduate (28)

>Degree (44)

Interactive website

n/a

Rozenblum et al., 2019 [72]

United States

Qualitative Focus groups

Adults (20–70 years) with a BMI of 27–35 kg/m² with internet access.

N = 13

A: Aged 20–70

F: 10 (77)

M: 3 (23)

African American (46)

White (31)

Other (8)

Missing (15)

>8th Grade (8)

High school (15)

College (54)

>Degree (23)

Interactive website

n/a

Sherwood et al., 2010 [73]

United States

RCT

Adults with a BMI between 30 and 39 kg/m² free of any health conditions & not participating in a weight loss programme

N = 63

INT 10 calls (n = 21)

INT 20 calls (n = 21)

CON (n = 21)

A: 49.5 ± 2.5

F: 50 (79)

M: 23 (21)

White (83)

College/ degree (58)

Professional (46)

Clerical/labour/other (54)

Telephone calls

INT: 20 × 10–20 min telephone calls delivered by a counsellor. Intervention lasted 10 Weeks.

COM: (1) Self-directed: received the same instructional

manual, pedometer & log booklets but not contacted

(2) Same intervention but only 10 (out of 20) contacts

Recruitment rate (63/187; 34%). Reason for decline was related to no contact info (38/124), not interested (7/124) and not eligible (79/124).

Retention for the self-directed: 16/21; 76%); 10 call group: (17/21; 81%); 20 call group (18/21; 86%).

Sessions completed: 0 (n = 1), 1–10 (n = 8), 11–19 (n = 6), 20 (n = 6). Increased contact associated with increased engagement (self-weighing, exercise).

Simpson et al., 2020 [74]

Scotland

RCT with mixed methods evaluation

Adults with a BMI ≥ 30 kg/m² who own a smartphone.

N = 109

INT (n = 73)

CON (n = 36)

A: 46.2 ± 10.6

F: 76 (70)

M: 33 (30)

White British/Irish (84)

White other (6)

Indian (2)

Pakistani (2)

Chinese (1)

Higher education (62)

Other (38)

Employed (94)

Unemployed (6)

mHealth App + interactive website

INT: Delivered by “Helpers”—People who the participant has nominated to support them. Intervention lasted 12 months.

COM: Received leaflet about health benefits of healthy eating/physical activity. No social support or personalised content.

Recruitment rate of those eligible (109/188; 56%). Reason for decline related to not meeting exclusion criteria (32/89), decline/non-response (40/89) and other reasons not specified (7/89).

Retention for the intervention group was 77% and the control group 71%.

Helper engagement with app was low, whereby only 54 (74%) downloaded the app and 48 (89%) used it twice or more. 28 helpers enrolled via the app, and 19 (36%) participants interacted with their helper(s) via the app.

Unick et al., 2019 [75]

United States

Pre-post study/Survey

Adults (aged 18–70) with a BMI ≥ 25 kg m² with internet access.

N = 119

A: 49.8 ± 9.8

F: 99 (83)

M: /

White Non-Hispanic (86)

Interactive website

INT: 4 x weekly sessions.

Recruitment rate not reported/unknown.

130 Enrolled, 119 completed with a retention rate of 91.5%.

Early non responders (4-week weight loss <2%) viewed 3.6 ± 0.8 with initial responders (4-week weight loss ≥2%) viewing 3.7 ± 0.9. Website logins (15.5 ± 12.4 vs. 18.5 ± 10.5), weight self-monitoring (26.8 ± 2.5 vs. 27.2 ± 2.2) and n days calorie intake was reported (26.4 ± 3.2 vs. 27.3 ± 2.4) were similar.

Van Beurden et al., 2018 [76]

England

Qualitative interviews

Adults (aged 35–60) with a BMI of 30–45 kg/m² and internet access.

N = 20

A: 35–37

F: 14 (70)

M: 6 (30)

/

Interactive website

INT: Primary care + web-based delivered by nutritionists and exercise instructors. Intervention lasted 4 weeks.

n/a

Vaz et al., 2020 [77]

United States

RCT

Aged (aged 18–65) with a BMI of 25–42 kg/m² employed in a sedentary job with access to a smartphone.

N = 28

INT (n = 13)

CON (n = 15)

A: 43.25 ± 2.48

F: 24 (86)

M: 4 (14)

African American (32)

Caucasian (43)

Hispanic (18)

Asian (7)

mHealth App + text messaging

INT: Primary care + web-based. Intervention lasted 6 months.

COM: Waitlist-control

Recruitment rate not reported/unknown.

100% retention at 6 months for all participants who did the intervention.

All participants engaged in all of the key components. Group chat messages sent was 0.36 ± 0.09 (mean ± SE) per day, n food photographs shared 0.41 ± 0.12 (mean ± SE) per day. Participants stepped on a smartscale 0.77 times per day with a daily weight rate of 0.47.

Voils et al., 2020 [78]

United States

Pre-post study with mixed methods evaluation

Veterans who have had bariatric surgery in the past 12 months

N = 30

A: 56.9 ± 10.0

F: 6 (20)

M: /

White (73)

Black (13)

Mixed/other (7)

>High school (100)

Employed (40)

Retired (40)

Unemployed (3)

Other (17)

Telephone calls

INT: Month 1: 4 x weekly calls, Month 2–4: 5 x biweekly calls (N = 9 calls), Phone calls addressed behaviour change strategies for diet, physical activity & supplement adherence followed by biweekly phone calls. Intervention lasted 16 weeks.

Recruitment rate of those eligible (33/69; 48%). Reason for decline not provided.

Retention at 16-week follow-up was 93% (28/30).

97% (29/30) participated in first telephone call. Mean number of calls received (out of a maximum of 9) was 7.8 (SD = 1.3). Participants who received <9 calls missed calls due to schedule difficulties rather than withdrawal.

Waring et al., 2018 [79]

United States

Pre-post study

Women (aged ≥18) between 6 weeks and 12 months postpartum, with a BMI of 25–45 kg/m² and access to a scale/smartphone and regularly use Facebook.

N = 19

A: 31.5 ± 3.2

F: 19 (100)

M: n/a

Non-Hispanic white (74)

Non-Hispanic black (5)

Hispanic/Latina (11)

Asian (11)

<Bachelor’s degree (11)

Bachelor’s/some graduate school (32)

Graduate degree (58)

Employed (64)

Student (5)

Stay-at-home parent (32)

Social networking group

INT: A Facebook group delivered by two coaches (a licensed clinical psychologist and a health promotion researcher), an obstetrician and a physical therapist. Intervention lasted 12 weeks.

Recruitment rate of those approached (19/134; 14%). Reason for decline included ineligible (40/115), no contact/decline (64/115), did not complete baseline (10/115) or did not join Facebook group (1/115).

High retention (95%; 18/19).

Participants posted median of 2 x posts and 24 replies and liked a median of 32 posts or comments. Engagement was sustained through the end of the intervention: 42% of participants posted, commented, or liked a post or comment on the last day of the intervention, 63% during the last week, and 100% in the last 4 weeks.

West et al., 2019 [80]

United StatesRCT

Women (aged ≥18 years) with a BMI of 25–50 kg/m² and in good general health

N = 32

Videoconference (n = 16)

Text message (n = 16)

A: 47.2 ± 12.4 years

F: 32 (100)

M: n/a

White (78)

African American (19)

Other (3)

Some college <4 years (9)

Vocational training (3)

College degree (44)

Graduate degree (44)

Video-conference

/Text messaging

INT: 1 x h weekly video-based sessions (N = 24 sessions) delivered by an experienced weight control counsellor. Intervention lasted 6 months.

COM: None

Recruitment rate of those approached (32/79; 41%). Reason for decline included not meeting inclusion criteria (46/47) and declining to participant (1/47).

Moderate retention at 2 (78%) and 6 (75%) months with no significant differences between conditions. More participants withdrew early in the study in the Text group (31%) compared to the Video (12%) group.

Video participants attended an average of 15 (62%) chat sessions, and Text participants attended an average of 12 (50%), with no significant difference between groups. Participants in the video condition self-monitored their weight on significantly more days (123 vs. 8 days) and reported physical activity significantly more often compared with those in the Text condition (55 vs. 22 days). No differences found for self-monitoring of dietary intake.

Women in the Video condition had significantly greater engagement, with greater self-monitoring and website utilisation than those in the Text condition.