Table 3 Feedback Characteristics

Ambeba et al., 2015; Burke et al., 2011; Burke et al., 2012; Conroy et al., 2011; Turk et al., 2013; Wang et al., 2012 [5, 27, 49, 50, 54, 55]

1) Weekly human feedback; 2) Weekly human feedback + Daily PDA feedback

Progress toward goal attainment related to diet, physical activity, and self-monitoring

Conditions 1 & 2: Written human feedback; Condition 2: Additional PDA-based feedback based on an algorithm delivered at a randomly-selected time

Conditions 1 & 2: Once a week for months 1–4, bi-weekly for months 5–12, once a month for months 13–18; Condition 2: Daily

Conditions 1 & 2: Not specified; Condition 2: 1–2 sentences

Conditions 1 & 2: Not specified; Condition 2: Messages included both positive reinforcement about the participant’s progress and guidance to direct behaviors to stay within goals

Beleigoli et al., 2020 [43]

1) Platform-only; 2) Platform + Coaching

Personalized goals

Condition 1: Study-designed website; Condition 2: Private forum embedded in the study website

Not specified

Not specified

Conditions 1 & 2: Behavioral feedback and suggestions of strategies for individualized goal achievement; Condition 2: Self-monitoring promotion, emotional social support, informative social support on diet quality and quantity, guiding in the development of action plans and of problem solving strategies

Burke et al., 2017 [42]

1) Feedback; 2) No feedback

Meeting dietary calorie, fat, and sugar goals; self-monitoring adherence

Condition 1: Study-designed app; Condition 2: N/A

Condition 1: 1–4 times per day; Condition 2: N/A

Condition 1: 1–3 sentences: Condition 2: N/A

Condition 1: Percentages of calories, fat and sugar that approximated various combinations of 1) under-eating, 2) meeting goals, or 3) exceeding goals; Condition 2: N/A

Burke et al., 2022 [28]

1) Feedback; 2) No feedback

Minutes of physical activity, diet, weight

Condition 1: Study-designed app; Condition 2: N/A

Condition 1: 3 times per day; Condition 2: N/A

Condition 1: 1–2 sentences based on the example; Condition 2: N/A

Condition 1: Addressed one behavior/outcome at a time; Condition 2: N/A

Blanson Henkemans et al., 2009 [40]

1) Computer assistant feedback; 2) No computer assistant feedback

Individualized lifestyle goals

Condition 1: An animated cat will look happy or sad depending on participant goal achievement; Condition 2: N/A

Not specified

Not specified

Condition 1: Expresses empathy about other priorities, positive reinforcement, explores discrepancies between lifestyle goal and current lifestyle; encourages self-efficacy and optimism; Condition 2: N/A

Fanning et al., 2017 [51]

1) Goal-setting + Feedback points; 2) Goal setting only; 3) Feedback points only; 4) None

Conditions 1–4: Physical activity; Condition 3: In-App activities

Conditions 1–4: Study-designed app

Conditions 1–4: Graphical feedback was continuously available; Conditions 1–3: Support emails were sent twice per week

Not specified

Conditions 1–4: Graphical feedback depicting intensity, enjoyment, number of bouts, minutes of activity completed within the week, progress toward goals; Conditions 1–2: Goal setting reminders, progress toward goals, activity summary table, reminders to be active; Condition 3: Points for in-app activity, increasingly fit avatar, new achievement level titles

Godino et al., 2013 [44]

1) Simple feedback; 2) Visual feedback; 3) Contextualized feedback

Physical activity

Conditions 1-3: Mailed letter

Single occurrence

1–4 pages

Conditions 1–3: Definition of physical activity, summary of physical activity's health benefits, current physical activity guidelines, participant's current physical activity level; Condition 2: Addition of line graphs of participant's heart rate and daily movement counts; Condition 3: Addition of possible ways to increase physical activity level

Jauho et al., 2015 [24]

1) Activity tracker with feedback; 2) Activity tracker with no feedback

Physical activity

Condition 1: On the device screen; Condition 2: N/A

Condition 1: Continuous; Condition 2: N/A

N/A

Condition 1: Accumulated daily moderate-vigorous physical activity time, time spent on different physical activity levels, steps, and calories burned for each day; Condition 2: N/A

Kerrigan et al., 2021 [46]

1) Daily feedback; 2) Weekly feedback

Steps

Conditions 1 & 2: Study-designed website, text message

Conditions 1 & 2: Continuous; Condition 1: Daily; Condition 2: Weekly

1–2 sentences based on the example

Condition 1: Established at midafternoon how close the participant was to meeting the goal; Condition 2: Summary of number of days out of the previous 7 that the goal was met

Kim et al., 2021 [53]

1) Tailored feedback about sedentary time; 2) Non-tailored feedback

Sedentary time

Conditions 1 & 2: Verbal

Twice during the study period

Not specified

Conditions 1 & 2: Education, general goal setting advice; Condition 1: Tailored goal setting based on self-monitored behavior, suggestions of non-sedentary behavior

Lawrie et al., 2018 [45]

1) Feedback; 2) No feedback

Physical activity

Condition 1: On the device screen; Condition 2: N/A

Condition 1: Continuous; Condition 2: N/A

N/A

Condition 1: Visual feedback; Condition 2: N/A

Lukkahatai et al., 2021 [25]

1) Visual feedback; 2) No feedback

Steps

Condition 1: On the device screen; Condition 2: N/A

Condition 1: Continuous; Condition 2: N/A

N/A

Condition 1: Step count; Condition 2: N/A

Martin et al., 2015 [26]

1) Feedback on upright time; 2) Feedback on sedentary time

Sedentary behavior; steps

Conditions 1 & 2: On the device screen: Condition 2: Vibration related to length of sitting time

Continuous

N/A

Condition 1: Percentage of upright time in green; Condition 2: Percentage of sitting time in yellow

Paschali et al., 2005 [52]

1) Feedback; 2) No feedback

Physical activity

Condition 1: Computer screen, printed report; Condition 2: N/A

Condition 1: Once per month (3 times); Condition 2: N/A

N/A

Condition 1: Graphical display; Condition 2: N/A

Prestwich et al., 2016 [48]

1) Goal setting + Self-monitoring; 2) Goal setting + Self-monitoring + Feedback

Physical activity

Condition 1: N/A; Condition 2: Text message

Daily

N/A

Condition 1: N/A; Condition 2: Graphical feedback with labels for daily and weekly activity units

Prestwich et al., 2017 [36]

1) Feedback; 2) No feedback; 3) Competition feedback

Physical activity

Conditions 1 & 3: Study-designed website; Condition 2: N/A

Weekly

N/A

Condition 1: Graphical display; Condition 2: N/A; Condition 3: League table of their position relative to other participants

Rabbi et al., 2015 [47]

1) Tailored feedback; 2) Generic feedback

Physical activity, diet

Conditions 1 & 2: Study-designed app

Daily

4 sentences

Condition 1: Positive feedback and suggestions for dietary and physical activity changes, tailored to context and person; Condition 2: Generic diet and physical activity suggestions

Tate et al., 2006 [41]

1) Automated feedback; 2) Human-generated feedback

Self-monitoring adherence; personalized calorie goal adherence; exercise goal adherence; weight loss

Conditions 1 & 2: Email

Weekly

Not specified

Condition 1: A feedback algorithm created a computer-tailored message of support, praise, comparison of behaviors with weight loss progress; and suggested behavioral strategies to improve self-monitoring adherence, calorie and exercise goal adherence, and weight loss; Condition 2: Clinical judgement to provide feedback on weekly weight loss compared with overall progress, progress toward behavioral goals, overcoming specific weight loss barriers, motivation, and answers to participants' questions

West et al., 2021 [29]

1) Pre-scripted feedback; 2) Human-generated feedback

Dietary monitoring, physical activity, self‐weighing

Conditions 1 & 2: Email

Weekly

Condition 1: 4 short paragraphs; Condition 2: Averaged 180 words

Condition 1: Pre‐scripted messages with three options (success, partial success, absence of self‐monitoring) regarding dietary monitoring, physical activity, self‐weighing; Condition 2: Positive reinforcement for successful goal achievement related to diet, physical activity, and weight self-monitoring, identified possible areas for improvement, and suggested possible strategies for identified challenges