A Theory-based Digital Intervention to Promote Weight Loss and Weight Loss Maintenance
- Conditions
- Overweight and Obesity
- Registration Number
- NCT04291482
- Lead Sponsor
- University of Social Sciences and Humanities, Warsaw
- Brief Summary
Obesity can severely reduce quality and longevity of life and there is an urgent need to help people lose weight and maintain weight loss long term. Digital behaviour change interventions targeting diet and physical activity have the potential for public health gain; however, these interventions are often not adequately tailored to the participants. The aim of this study is to develop and test a digital intervention to help people make sustainable changes to diet and physical activity, and consequently their weight. This study is a hybrid trial that will evaluate the effectiveness, cost-effectiveness and implementation of the Choosing Health program among overweight/obese adults.
This study is a two-group randomised controlled trial (RCT) with within person assessment. Participants (N=285) will be randomly assigned to either the Choosing Health digital intervention or a control group. For intervention participants, Ecological Momentary Assessment (EMA) will be used to identify behavioural determinants for each individual in order to tailor evidence-based behaviour change techniques and intervention content. Control group will receive non-tailored factual weight loss advice. Primary outcome is mean difference in weight loss between groups at 6 months, in kilograms. Key outcomes will be measured at baseline, 3-, 6- and 12 months. Data will be analysed using multilevel modelling and time series analysis.
This is the first weight loss intervention applying individualised digital tailoring based on continuous assessment of individual's psychological determinants of behaviour measured over time. The Choosing Health will offer insight into factors associated with success in making sustained changes to weight, and secondary outcomes, such as diet and physical activity.
- Detailed Description
Behavioural science offers theory-driven and evidence-based behaviour change techniques that can support people in losing weight and maintaining it long term. These techniques have not yet been assessed in within-person studies that not only examine aggregated between-group effects (e.g., intervention versus control comparisons) but also determine personal trajectories of weight loss and maintenance and tailor accordingly to the strongest predictors of outcomes. The aim of the proposed study is to develop and test a digital intervention that uses Ecological Momentary Assessment (EMA) and tailors the evidence-based behaviour change techniques that are based on theory to the strongest predictors of outcomes (based on EMA responses collected over time).
This study will determine the effectiveness and cost-effectiveness of the proposed intervention through the Randomised Controlled Trial (EMA tailored intervention versus control), with within person component embedded in the trial. Study hypothesis is that participants in the EMA tailored intervention group will lose significantly more weight than participants in the control group from baseline to 6 months (post program comparison - primary outcome) and at 12 months (maintenance effects assessment - secondary outcome).
This is a two-group intervention trial adopting a randomised controlled design. It is a hybrid trial assessing intervention effectiveness, cost-effectiveness and implementation. This study has within person component embedded in the design and intervention group will answer EMA questions during the initial 3 months of the study and will receive tailored intervention at month 3 combined with additional EMA. There are two phases of the 6-month intervention (I) observational EMA phase and (II) active intervention phase.
The proposed intervention is delivered online through emails and text messages and based on the EMA responses in phase I, it is tailored in phase II. The intervention will have a non-automatic component, meaning trained facilitators will answer participants' queries and provide additional resources if and when needed to improve the engagement with the intervention. The study meets CONSORT criteria for RCTs and study ethical approval was obtained from SWPS University of Social Sciences and Humanities, Wroclaw, Poland (approval number 03/P/12/2019).
Recruitment & Eligibility
- Status
- UNKNOWN
- Sex
- All
- Target Recruitment
- 285
- Adults with overweight and obesity (18+);
- Individuals with a BMI 25 and higher at the baseline assessment.
- Individuals who self-report a physical condition or impairment preventing them from being physically active or losing excess body weight;
- Individuals who have had a bariatric surgery or are planning to have one within the next 12 months;
- Individuals who are currently participating in another weight loss program (e.g., regular meetings with personal trainer);
- Individuals who report any contradictions to exercise as indicated by the PAR-Q or pregnant women who consulted their doctor to obtain approval to take part in the study and did not get the approval;
- Individuals who do not have a mobile phone with access to the internet;
- Individuals who are currently participating in another weight loss program (e.g., regular meetings with personal trainer);
- Pregnant women;
- Individuals who are planning to move outside of the study region and are not willing to travel for study measurement sessions;
- Individuals who are on medication that causes weight gain;
- Individuals with a pacemaker (the scale used in the study is not appropriate for use in these individuals).
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Primary Outcome Measures
Name Time Method Weight Change from baseline to 6 months Mean difference in weight loss between groups at 6 months, in kilograms
- Secondary Outcome Measures
Name Time Method Height baseline (Time 0), 3 months (Time 1), 6 months (Time 2) and 12 months (Time 3) Objective measures of height in centimetres
Number of adverse effects Through study completion, an average of 1 year report of any adverse effects that may occur during the intervention
Self-reported measures of goal conflict baseline (Time 0), 3 months (Time 1), 6 months (Time 2) and 12 months (Time 3) Theory-derived psychological construct measured with 2 items addressing goal conflict (1-5 scale), the minimum and maximum values for the scale are 2-10, and higher scores mean a worse outcome (higher goal conflict)
Weight baseline (Time 0), 3 months (Time 1), 6 months (Time 2) and 12 months (Time 3) Objective measures of weight in kilograms
Diet baseline (Time 0), 3 months (Time 1), 6 months (Time 2) and 12 months (Time 3) Measured with the Dietary Instrument for Nutrition Education (fatty foods, fruit and vegetable, and sugary food consumption). High scores are indicative of high consumption. Higher scores for fruit and vegetable mean a better outcome (0-3 scale; 1 item) and higher scores for fatty foods (0-24; 8 items on 0-3 scale) and sugary food (0-9; 3 items on 0-3 scale) mean a worse outcome. The minimum values are 0 and the maximum values are specified above in brackets.
Physical activity (self-reported) and sitting time baseline (Time 0), 3 months (Time 1), 6 months (Time 2) and 12 months (Time 3) Measured with the International Physical Activity Questionnaire short version, the minimum value is 0 (no activity), higher scores mean a better outcome. All activity will be converted to minutes before calculating MET minutes (total score). In each category a maximum of 21 hours of activity are permitted a week (3 hours X 7 days). To calculate MET minutes a week the MET value given (walking = 3.3, moderate activity = 4, vigorous activity = 8) will be multiplied by the minutes the activity was carried out and again by the number of days that that activity was undertaken. To get total MET minutes of physical activity a week the MET minutes achieved in each category (walking, moderate activity and vigorous activity) will be added.
Body fat % baseline (Time 0), 3 months (Time 1), 6 months (Time 2) and 12 months (Time 3) Objective measures of body fat %
Self-reported measures of motivation baseline (Time 0), 3 months (Time 1), 6 months (Time 2) and 12 months (Time 3) Theory-derived psychological construct measured with 2 items addressing motivation (1-5 scale), the minimum and maximum values for the scale are 2-10, and higher scores mean a better outcome (higher motivation).
Self-reported measures of self-efficacy baseline (Time 0), 3 months (Time 1), 6 months (Time 2) and 12 months (Time 3) Theory-derived psychological construct measured with 2 items addressing self-efficacy (1-5 scale), the minimum and maximum values for the scale are 2-10, and higher scores mean a better outcome (higher self-efficacy).
Self-reported measures of attitudes baseline (Time 0), 3 months (Time 1), 6 months (Time 2) and 12 months (Time 3) Theory-derived psychological construct measured with 2 items addressing attitudes (1-5 scale), the minimum and maximum values for the scale are 2-10, and higher scores mean a better outcome (higher attitudes).
Self-reported measures of action planning baseline (Time 0), 3 months (Time 1), 6 months (Time 2) and 12 months (Time 3) Theory-derived psychological construct measured with 8 items addressing action planning (1-5 scale), the minimum and maximum values for the scale are 8-40, and higher scores mean a better outcome (better action planning).
Self-reported measures of coping planning baseline (Time 0), 3 months (Time 1), 6 months (Time 2) and 12 months (Time 3) Theory-derived psychological construct measured with 6 items addressing action planning (1-5 scale), the minimum and maximum values for the scale are 6-30, and higher scores mean a better outcome (better coping planning).
Systolic and diastolic blood pressure baseline (Time 0), 3 months (Time 1), 6 months (Time 2) and 12 months (Time 3) Objective measures of systolic and diastolic blood pressure measured in units of millimeters of mercury (mmHg)
Alcohol baseline (Time 0), 3 months (Time 1), 6 months (Time 2) and 12 months (Time 3) Measured with the Audit C; scale 0-12, high scores are indicative of high consumption.
Health related quality of life baseline (Time 0), 3 months (Time 1), 6 months (Time 2) and 12 months (Time 3) Measured with the EQ-5D-5 L (this is the unabbreviated scale title), the scale has five domains each scored on 1-5 scale; min 5 maximum 25 for all domains combined) higher scores mean a worse outcome and visual analogue scale is the second part of the questionnaire, asking to mark health status on the day of the interview on a 20 cm vertical scale with end points of 0 and 100. There are notes at the both ends of the scale that the bottom rate (0) corresponds to " the worst health you can imagine", and the highest rate (100) corresponds to "the best health you can imagine".
BMI baseline (Time 0), 3 months (Time 1), 6 months (Time 2) and 12 months (Time 3) Weight and height will be combined to report BMI in kg/m\^2
Sleep duration and quality baseline (Time 0), 3 months (Time 1), 6 months (Time 2) and 12 months (Time 3) Measured with the Pittsburgh Sleep Quality Index. In scoring the Pittsburgh Sleep Quality Index, seven component scores are derived, each scored 0 (no difficulty) to 3 (severe difficulty). The component scores are summed to produce a global score (range 0 to 21). Higher scores indicate worse sleep quality.
Self-reported measures of intentions baseline (Time 0), 3 months (Time 1), 6 months (Time 2) and 12 months (Time 3) Theory-derived psychological construct measured with 2 items addressing intentions (1-5 scale), the minimum and maximum values for the scale are 2-10, and higher scores mean a better outcome (higher intentions).
Self-reported measures of goal facilitation baseline (Time 0), 3 months (Time 1), 6 months (Time 2) and 12 months (Time 3) Theory-derived psychological construct measured with 2 items addressing goal facilitation (1-5 scale), the minimum and maximum values for the scale are 2-10, and higher scores mean a better outcome (better goal facilitation)
Self-reported measures of habit strength for physical activity baseline (Time 0), 3 months (Time 1), 6 months (Time 2) and 12 months (Time 3) Theory-derived psychological construct measured with h self-report behavioural automaticity index for physical activity, 4 items (1-5 scale); the minimum and maximum values for the scale are 4-20, and higher scores mean a better outcome (habit strength)
Self-reported measures of habit strength for healthy eating baseline (Time 0), 3 months (Time 1), 6 months (Time 2) and 12 months (Time 3) Theory-derived psychological construct measured with self-report behavioural automaticity index for healthy eating, 4 items (1-5 scale); the minimum and maximum values for the scale are 4-20, and higher scores mean a better outcome (habit strength)
Trial Locations
- Locations (1)
SWPS University
🇵🇱Wroclaw, Slaskie, Poland
SWPS University🇵🇱Wroclaw, Slaskie, Poland