Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12623000338662
Ethics application status
Approved
Date submitted
17/03/2023
Date registered
31/03/2023
Date last updated
29/04/2024
Date data sharing statement initially provided
31/03/2023
Date results information initially provided
29/04/2024
Type of registration
Prospectively registered

Titles & IDs
Public title
Comparison of two weight loss programs involving 16 weeks on a severely energy-restricted diet in adults with overweight or obesity: The TANGO Diet Trial (Temporary phases of Accelerated weight loss for Noticeably Greater Outcomes)
Scientific title
Comparison of two weight loss programs involving 16 weeks on a severely energy-restricted diet in adults with overweight or obesity: The TANGO Diet Trial (Temporary phases of Accelerated weight loss for Noticeably Greater Outcomes)
Secondary ID [1] 308097 0
None
Universal Trial Number (UTN)
U1111-1289-8605
Trial acronym
The TANGO Diet Trial
Linked study record

Health condition
Health condition(s) or problem(s) studied:
obesity 327790 0
overweight 327791 0
cardiovascular disease 329378 0
osteoporosis 329379 0
sarcopenia 329380 0
binge eating 329381 0
mood disorders 329382 0
Condition category
Condition code
Diet and Nutrition 324861 324861 0 0
Obesity
Diet and Nutrition 324862 324862 0 0
Other diet and nutrition disorders
Cardiovascular 326322 326322 0 0
Coronary heart disease
Cardiovascular 326323 326323 0 0
Diseases of the vasculature and circulation including the lymphatic system
Cardiovascular 326324 326324 0 0
Hypertension
Musculoskeletal 326327 326327 0 0
Osteoporosis
Musculoskeletal 326328 326328 0 0
Other muscular and skeletal disorders
Mental Health 326329 326329 0 0
Eating disorders
Mental Health 326330 326330 0 0
Anxiety
Mental Health 326331 326331 0 0
Depression

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
The test intervention for this research trial will be a 53-week weight loss program involving 16 weeks on a severe diet. A severe diet is defined in this research trial as a medically supervised diet that induces fast weight loss (approximately 0.5 to 2 kilograms per week), achieved by replacing all regular meals and snacks with nutritionally replete meal replacement products, such as shakes. The meal replacement products will be provided to participants by the research trial at no cost to participants. In addition to 16 weeks on the severe diet (using meal replacement products), the 53-week weight loss program will involve 6 weeks of transition from meal replacement products to regular food, and 31 weeks of weight stabilisation on regular food.

After the 16 weeks on the severe diet, participants will be encouraged to adhere to a diet that follows the Australian dietary guidelines, which provide up-to-date advice about the amounts and kinds of foods to eat for health and wellbeing, based on the latest high-quality scientific evidence. To aid adherence to the Australian dietary guidelines, participants will be provided with a personal healthy eating plan from the Eat for Health Program that is associated with the Australian dietary guidelines. The personal healthy eating plan will advise each participant on how many serves to consume per day of foods from each of Five Food Groups defined in the Eat for Health Program (vegetables and legumes/beans; fruit; grain (cereal) foods, mostly wholegrain and/or high fibre cereal varieties; lean meats and poultry, fish, eggs, tofu, nuts and seeds, and legumes/beans; milk, yoghurt, cheese and/or alternatives, mostly reduced fat), and will include an allowance for unsaturated spreads and oils or discretionary choices. The personal healthy eating plan for each participant will be developed in conjunction with advice to the research team from an external Accredited Practising Dietitian, and will be based on each participant’s sex, age, height, physical activity levels and food preferences, and whether the participant aims to lose weight or remain weight-stable during the weight stabilisation phase.

Participants will be encouraged to weigh themselves regularly throughout the entire 53-week weight loss program (e.g., every day), and to adjust their dietary intake, if necessary, in order to either lose weight or remain weight stable.

Participants will be supported through the 53-week weight loss program with a series of weekly or fortnightly live online group support sessions (33 sessions in total over 53 weeks). Of these 33 live online group support sessions, 10 to 11 will be delivered during the 16 weeks on the severe diet, 4 to 6 will be delivered during the 6 weeks of transition to regular food, and 16 to 19 to will be delivered during the 31 weeks of weight stabilisation on regular food. The sessions will cover topics that are known to be of value for weight loss programs, such as: how to follow the severe diet; how to transition from a severe diet to a food-based diet; navigating social situations while on a severe diet or healthy eating plan; awareness of unhelpful thinking styles; getting social support; and setting progressive targets for physical activity based on gradually building up to the types and amounts of physical activity as recommended by the World Health Organisation. Outside the provision of meal replacement products and the 33 live online group support sessions, no other intervention components will be delivered as part of the weight loss program.

The live online group support sessions will be facilitated by the Chief Investigator, Prof. Amanda Salis, accompanied by one or more professionals with expertise relevant to the session topic (e.g., a doctor with expertise in the treatment of high body mass index during sessions about the severe diet, an Accredited Practicing Dietitian or Registered Nutritionist during sessions about following the Australian dietary guidelines, a psychologist registered with the Psychology Board of Australia during sessions about thinking styles, a counsellor who is a member of the Australian Counselling Association during sessions about effective interpersonal communication, and an Accredited Exercise Physiologist during sessions about physical activity).

The live online group support sessions will be 45 minutes in duration. The first half (20 to 25 minutes) will be dedicated to instruction about the weight loss program and will be recorded and subsequently emailed to participants, so participants can watch the session ‘on-demand’ instead of live, if desired. The remaining 20 to 25 minutes will not be recorded, and will be dedicated to a facilitated discussion about participants’ experiences of and Q+A about the weight loss program.

Each participant will be in a group with of up to 20 other participants for the live online group support sessions. They will be with the same group of participants for all 33 sessions in the 53-week weight loss program. Some of the sessions will involve only participants in that participant’s own group (i.e., a total of up to 21 participants). Some of the sessions will also involve participants from other groups besides the participant’s own group. Specifically, up to 3 other groups (i.e., a total of up to 84 participants) during the severe diet and the transition to regular food, and up to 6 other groups (i.e., a total of up to 147 participants) during the weight stabilization phase. There will be a ratio of 1 facilitator for every 15 participants attending each live online group support session.

Adherence to the weight loss program will be estimated in two ways: firstly, by investigating changes in weight over time; and secondly, by asking participants to bring back to the research facility the packages of meal replacement products that had been given to them in a previous visit, regardless of whether those packages are empty or not, and by counting how many of the packages have been emptied (an indicator of use). Changes in weight over time will be estimated by emailing participants once a week with a link to a secure online self-report survey and a request to weigh themselves upon rising the next day and to enter their weight and upload an image of the scales showing that weight on the display in the self-report survey.
Intervention code [1] 324544 0
Lifestyle
Comparator / control treatment
The control intervention for this research trial will be similar to the test intervention: it will be a 53-week weight loss program that also involves 16 weeks on a severe diet (with all meal replacement products provided to research participants by the research trial at no cost to participants) followed by transition to a personal healthy eating plan from the Eat for Health Program that is associated with the Australian dietary guidelines, and will also be supported by 33 live online group support sessions every 1 to 2 weeks with the same facilitators and professionals and topics and physical activity guidelines. We are not able to publicly disclose the difference between the two weight loss programs under investigation in this research trial, because knowledge among participants of the difference may influence the results. However, both weight loss programs are expected to be equally effective for weight loss in the shorter term (26 weeks, which is 6 months). We do not yet know whether one of these two weight loss programs will be more effective for weight loss in the longer-term (53 weeks, 104 weeks, 156 weeks and 260 weeks, which is 12 months, 24 months, 36 months and 60 months [5 years]).
Control group
Active

Outcomes
Primary outcome [1] 332677 0
Weight loss (per cent of baseline), determined from weight measured by research team members in the research facility using a calibrated digital scale
Timepoint [1] 332677 0
0, 16, 22, 26, 53 (primary timepoint) and 104 weeks after commencement of the interventions
Secondary outcome [1] 414339 0
Waist circumference, measured by a member of the research team using an inelastic tape measure
Timepoint [1] 414339 0
0, 16, 22, 26, 53 and 104 weeks after commencement of the interventions
Secondary outcome [2] 419718 0
Hip circumference, measured by a member of the research team using an inelastic measuring tape
Timepoint [2] 419718 0
0, 16, 22, 26, 53 and 104 weeks after commencement of the interventions
Secondary outcome [3] 419719 0
Fat mass, measured by dual energy X-ray absorptiometry of the whole body
Timepoint [3] 419719 0
0, 16, 22, 26, 53 and 104 weeks after commencement of the interventions
Secondary outcome [4] 419728 0
Cardiometabolic risk score, as determined from a composite of the following outcomes: waist circumference (measured by a member of the research team using an inelastic measuring tape); use of antihypertensive medication (yes or no, asked by a member of the research team); family history of premature myocardial infarction, defined as 1st degree relative with myocardial infarction before age 60 (yes or no, also asked by a member of the research team); currently smoking (yes or no, as determined by self-report); blood pressure (measured by a member of the research team using a digital sphygmomanometer; and circulating concentrations of glucose, glycosylated hemoglobin, insulin, triglycerides, cholesterols (total, low and high density lipoprotein), and high-sensitivity C-reactive protein, determined in blood samples collected in the research facility and tested by a commercial pathology laboratory.
Timepoint [4] 419728 0
0, 26, 53 and 104 weeks after commencement of the interventions
Secondary outcome [5] 419729 0
Bone mineral density, measured using dual energy X-ray absorptiometry (DXA) of the total hip
Timepoint [5] 419729 0
0, 26, 53, and 104 weeks after commencement of the interventions
Secondary outcome [6] 419730 0
Bone mineral density, measured using dual energy X-ray absorptiometry (DXA) of the femoral neck
Timepoint [6] 419730 0
0, 26, 53, and 104 weeks after commencement of the interventions
Secondary outcome [7] 419731 0
Bone mineral density, measured using dual energy X-ray absorptiometry (DXA) of the total body
Timepoint [7] 419731 0
0, 26, 53, and 104 weeks after commencement of the interventions
Secondary outcome [8] 419732 0
Lean mass, measured using dual energy X-ray absorptiometry (DXA) of the total body
Timepoint [8] 419732 0
0, 16, 22, 26, 53 and 104 weeks after commencement of the interventions
Secondary outcome [9] 419733 0
Muscle strength (hand grip strength), measured using a hand-held dynamometer
Timepoint [9] 419733 0
0, 16, 22, 26, 53 and 104 weeks after commencement of the interventions
Secondary outcome [10] 419734 0
Resting energy expenditure, as determined using indirect calorimetry
Timepoint [10] 419734 0
0, 16, 22, 26, 53 and 104 weeks relative to the start of the weight loss interventions
Secondary outcome [11] 420010 0
Binge eating behaviours, as assessed using the Eating Disorders Examination Questionnaire (EDEQ), delivered using a self-report survey
Timepoint [11] 420010 0
0, 26, 53, 104, 156 and 260 weeks after commencement of the interventions
Secondary outcome [12] 420011 0
Loss of control over eating, as assessed using the Loss of Control over Eating Scale (LOCES), delivered using a self-report survey
Timepoint [12] 420011 0
0, 26, 53, 104, 156 and 260 weeks after commencement of the interventions
Secondary outcome [13] 420012 0
Food addiction, as assessed using the Yale Food Addiction Scale, delivered using a self-report survey
Timepoint [13] 420012 0
0, 26, 53, 104, 156 and 260 weeks after commencement of the interventions
Secondary outcome [14] 420013 0
Eating disorders, as assessed using the questions pertaining to eating disorders in the Mini International Neuropsychiatric Interview (MINI), delivered via a self-report survey
Timepoint [14] 420013 0
0, 26, 53, 104, 156 and 260 weeks after commencement of the interventions
Secondary outcome [15] 420014 0
Self esteem, as assessed using the Rosenberg Self-Esteem Scale, delivered via self-report survey
Timepoint [15] 420014 0
0, 26, 53, 104, 156 and 260 weeks after commencement of the interventions
Secondary outcome [16] 420015 0
Quality of life, as assessed using the RAND 36-Item Short Form Survey (SF-36), delivered via self-report survey
Timepoint [16] 420015 0
0, 26, 53, 104, 156 and 260 weeks after commencement of the interventions
Secondary outcome [17] 420016 0
Mood, assessed using the Depression, Anxiety and Stress Scale (DASS-21), delivered via self-report survey
Timepoint [17] 420016 0
0, 26, 53, 104, 156 and 260 weeks after commencement of the interventions
Secondary outcome [18] 420017 0
Locus of control, as assessed using the Multidimensional Health Locus of Control (Form C), delivered via self-report survey
Timepoint [18] 420017 0
0, 26, 53, 104, 156 and 260 weeks after commencement of the interventions
Secondary outcome [19] 420018 0
Drive to eat, as assessed using the following self-report instrument administered in our research facility: General Food Craving Questionnaire – State
Timepoint [19] 420018 0
0, 16, 22, 26, 53 and 104 weeks after commencement of the interventions
Secondary outcome [20] 420019 0
Drive to eat, as assessed using the following self-report instruments administered in our research facility: Control of Eating Questionnaire – Today
Timepoint [20] 420019 0
0, 16, 22, 26, 53 and 104 weeks after commencement of the interventions
Secondary outcome [21] 420020 0
Drive to eat, as assessed using the following self-report instrument administered in our research facility: Control of Eating Questionnaire – 7 Days
Timepoint [21] 420020 0
0, 16, 22, 26, 53 and 104 weeks after commencement of the interventions
Secondary outcome [22] 420021 0
Drive to eat, as assessed using the following self-report instrument administered in our research facility: Eating Self-Efficacy Scale
Timepoint [22] 420021 0
0, 16, 22, 26, 53 and 104 weeks after commencement of the interventions
Secondary outcome [23] 420022 0
Drive to eat, as assessed using the following self-report instrument administered in our research facility: Subjective drive to eat (visual analogue scales) – fasting
Timepoint [23] 420022 0
0, 16, 22, 26, 53 and 104 weeks after commencement of the interventions
Secondary outcome [24] 420023 0
Plasma concentrations of ghrelin
Timepoint [24] 420023 0
0, 26, 53 and 104 weeks relative to the start of the interventions
Secondary outcome [25] 420024 0
Plasma concentrations of peptide YY
Timepoint [25] 420024 0
0, 26, 53 and 104 weeks relative to the start of the interventions
Secondary outcome [26] 420025 0
Plasma concentrations of leptin
Timepoint [26] 420025 0
0, 26, 53 and 104 weeks relative to the start of the interventions
Secondary outcome [27] 420026 0
Circulating ketone concentrations, as determined from capillary blood
Timepoint [27] 420026 0
0, 16, 22, 26, 53 and 104 weeks after commencement of the interventions
Secondary outcome [28] 420027 0
Subjective drive to eat, measured using visual analogue scales administered via a self report survey that participants will be requested to do in the fasted state before breakfast in their own environment (i.e., not in our research facility)
Timepoint [28] 420027 0
Before commencement of the interventions (0 weeks), then every 1 to 2 weeks throughout the 53-week interventions (33 timepoints), then again at 104, 156 and 260 weeks after commencement of the interventions
Secondary outcome [29] 420028 0
Side effects of the weight loss program, as determined using an in-house Diet Side Effects Survey, delivered via self-report
Timepoint [29] 420028 0
Before commencement of the interventions (0 weeks), then every 1 to 2 weeks throughout the 16 weeks on the severe diet (10-11 timepoints), then again every 1-8 weeks throughout the remainder of the 53-week intervention
Secondary outcome [30] 420029 0
Weight, measured by participants in their own home upon rising for the day and in the fasted state (e.g., in the morning before breakfast). Participants will be asked to enter their weight into an online data collection instrument, along with a photograph of the scale showing the number they have entered.
Timepoint [30] 420029 0
Before commencement of the interventions (0 weeks), then every 1 to 2 weeks throughout the 53-week interventions (33 timepoints), then again at 104, 156 and 260 weeks after commencement of the interventions
Secondary outcome [31] 420030 0
Physical activity as determined by use of an accelerometer for 7 days
Timepoint [31] 420030 0
0, 26, 53 and 104 weeks relative to the start of the interventions
Secondary outcome [32] 420031 0
Sleep, as determined by use of an accelerometer for 7 days
Timepoint [32] 420031 0
0, 26, 53 and 104 weeks relative to the start of the interventions
Secondary outcome [33] 420032 0
Self-efficacy to regulate exercise, as determined by a self-report survey of the same name
Timepoint [33] 420032 0
0, 26, 53, and 104 weeks relative to the start of the interventions
Secondary outcome [34] 420033 0
Sleep, as determined in the following self-report survey: Epworth Sleepiness Scale
Timepoint [34] 420033 0
0, 26, 53 and 104 weeks relative to the start of the interventions
Secondary outcome [35] 420034 0
Sleep, as determined in the following self-report survey: Pittsburgh Sleep Quality Index
Timepoint [35] 420034 0
0, 26, 53 and 104 weeks relative to the start of the interventions
Secondary outcome [36] 420035 0
Sleep, as determined in the following self-report survey: Multivariable Apnoea Prediction Index
Timepoint [36] 420035 0
0, 26, 53 and 104 weeks relative to the start of the interventions
Secondary outcome [37] 420036 0
Diet quality, as determined using a self-report survey
Timepoint [37] 420036 0
0 and 53 weeks relative to the start of the interventions
Secondary outcome [38] 420037 0
Height, measured using a wall-mounted stadiometer by a member of the research team in our research facility
Timepoint [38] 420037 0
0 and 104 weeks relative to the start of the interventions
Secondary outcome [39] 420038 0
Exploratory outcomes will additionally be investigated in this trial as part of PhD projects. They are listed here in a single field, because a maximum of 40 outcomes can be listed in this website.

Muscle thickness (quadriceps femoris group of muscles), measured using ultrasound of the front of the thigh

Muscle function (quadriceps femoris group of muscles), measured using a Biodex System 3 dynamometer. Specifically, the absolute and relative isokinetic peak torque, angle of peak torque, average power and total work during concentric and eccentric actions will be measured in a seated position

Functional mobility, measured using the timed up and go (TUG) test, the 30-second sit-to-stand test (30STS), the timed stair climb (SCT), and the 6-minute walk test (6MWT)

Balance, measured using a force plate under the feet while standing still (with eyes open and with eyes closed), as well as while moving (i.e., during the timed up and go test)

Subcutaneous adipose tissue thickness, measured using ultrasound across 7 sites (chest, scapula, axilla, tricep, waist, hip, and thigh)
Timepoint [39] 420038 0
0, 16, 22, 53 and 104 weeks after commencement of the interventions

Eligibility
Key inclusion criteria
18-70 years of age

Body mass index (BMI) equal to or greater than 30 kg/m2 or BMI equal to or greater than 27 kg/m2 if disease risk factors and/or obesity-related comorbidities are present

Able to attend our facility 17 times over the 104-week (24-month) clinical trial (15 times in the first 53 weeks (12 months)

Weight stable for at least 1 month (± 2 kg) before commencement of the severe diet

Living in the Perth metropolitan area

Able to understand written and spoken English

Have access to an email account

Have access to a computer (either a smartphone, laptop or desktop) and the Internet
Minimum age
18 Years
Maximum age
70 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Type 1 diabetes

Pregnancy (or breastfeeding)

Pregnancy planned in the next 2 years

Schizophrenia

Diagnosed eating disorder

A score on the Alcohol Use Disorders Identification Test – Consumption (AUDIT-C) of equal to or greater than 6 (for female adults) or equal to or greater than 7 (for male adults)

Unwillingness to abstain from the consumption of alcohol during the 16-week severe diet

Use within the past 6 months of any illegal or recreational drugs

Severe/advanced kidney disease

Severe/advanced liver disease

Porphyria

Recent myocardial infarction (3 months)

Recent cerebrovascular event (3 months)

Recent commencement of anticoagulant (e.g., warfarin) treatment (3 months)

Current fluid restriction treatment

Unstable angina

Lactose intolerance

Strict veganism

Unwillingness to consume the meal replacement products to be provided by the research trial for 16 weeks

Previous bariatric surgery

Bariatric surgery planned in the next 2 years

Recent involvement in another clinical trial (3 months)

Involvement in another clinical trial planned in the next 2 years

Tobacco or vape use in the past 6 months

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Allocation will be concealed from the the person(s) who determine if a person is eligible for inclusion in the trial because they will be unaware, when this decision is made, to which group the subject will be allocated. Allocation will be concealed by use of central randomisation by computer.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Minimisation will be used to avoid imbalance between groups in major known covariates. Thus, participants will be stratified by BMI (<35 and >=35 kg/m2), age (<40 and >=40 years), sex, and diabetes status.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s


The people analysing the results/data
Intervention assignment
Parallel
Other design features
Not applicable
Phase
Not Applicable
Type of endpoint/s
Safety/efficacy
Statistical methods / analysis
This trial will involve 288 adults who will be randomised into 2 groups with 144 participants in each: Program 1 and Program A.

This sample size of 288 has been calculated in order to detect a 3% or greater increment in weight loss as a per cent of baseline at 53 weeks, with a standard deviation of 7%, an alpha of 5%, 90% power, using a 2-sided test and allowing for up to 20% attrition between baseline and 53 weeks (230 x 1.25 = 288 participants, or 144 in each arm).

Published studies – including systematic reviews – of weight loss programs involving a severe diet in similar populations have reported mean weight losses of 6-11% at 52 weeks after commencement of the program, with a standard deviation of 6-8%. Similarly, our previous research trials involving severe diets with durations of 8-16 weeks (NHMRC Project Grants 1026005 and 1067771) have resulted in mean weight losses of 10-15% of baseline weight at 52 weeks, with a standard deviation of 6.6-7.0%. In the currently proposed superiority trial, we hypothesize that that there will be a >=3% greater reduction in body weight between the two weight loss programs at 53 weeks (e.g., a mean weight loss of 15% of baseline in one group versus 18% in the other). A 3% greater reduction in body weight would be clinically relevant, because the benefits of weight loss are dose-dependent, becoming apparent after loss of as little as 3% of baseline body weight. The Therapeutic Goods Administration mandates that to be considered effective for weight loss, listed medicines must demonstrate a loss of at least 5% of initial bodyweight and at least 3% greater reduction in body weight than placebo.

Data analysis will be done using intention to treat principles. The primary outcome (weight loss as a percent of baseline at 53 weeks) will be compared between the two weight loss programs using a Student’s t-test, as will secondary outcomes that are also continuous variables. Comparison of categorical variables will be done using the Chi squared test. Exploratory analyses will be performed using appropriate statistical methods, both univariate and multivariate, including multiple regression and time to event outcomes using proportional hazard models.

Recruitment
Recruitment status
Active, not recruiting
Date of first participant enrolment
Anticipated
6/04/2023
Actual
12/05/2023
Date of last participant enrolment
Anticipated
25/01/2024
Actual
30/01/2024
Date of last data collection
Anticipated
10/03/2029
Actual
Sample size
Target
288
Accrual to date
Final
304
Recruitment in Australia
Recruitment state(s)
WA

Funding & Sponsors
Funding source category [1] 312353 0
Government body
Name [1] 312353 0
National Health and Medical Research Council
Country [1] 312353 0
Australia
Primary sponsor type
University
Name
The University of Western Australia
Address
35 Stirling Highway
Crawley WA 6009
Country
Australia
Secondary sponsor category [1] 313918 0
None
Name [1] 313918 0
Address [1] 313918 0
Country [1] 313918 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 311716 0
University of Western Australia Human Research Ethics Committee
Ethics committee address [1] 311716 0
35 Stirling Highway
Crawley WA 6009
Ethics committee country [1] 311716 0
Australia
Date submitted for ethics approval [1] 311716 0
10/10/2022
Approval date [1] 311716 0
20/02/2023
Ethics approval number [1] 311716 0

Summary
Brief summary
The purpose of this research trial is to compare the long-term effectiveness of two weight loss programs involving a severe diet.

A severe diet is defined in this research trial as a medically-supervised diet that induces fast weight loss (approximately 0.5 to 2 kilograms per week), achieved by replacing all regular meals and snacks with nutritionally replete meal replacement products, such as shakes. Research reveals surprising benefits of severe diets, including: motivation associated with fast weight loss; hunger control; pain reduction; and mood improvements, among other benefits. However, keeping weight off after a severe diet – or indeed after any weight loss diet – is difficult for most people.

This research trial will compare two weight loss programs that involve a severe diet. The two weight loss programs are referred to in this research trial as ‘Program 1’ and ‘Program A’. Both weight loss programs are 53 weeks (12 months) in duration, and both involve up to 16 weeks (4 months) on a severe diet. Both weight loss programs are expected to be equally effective for weight loss in the short term (26 weeks, which is 6 months). We do not yet know whether one of these two weight loss programs will be more effective for weight loss in the long-term (53 weeks, 104 weeks, 156 weeks and 260 weeks, which is 12 months, 24 months, 36 months and 60 months).
Trial website
https://www.uwa.edu.au/projects/tango
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 122110 0
Prof Amanda Salis
Address 122110 0
Building 444
Mailbag Delivery Point (MBDP) M408
School of Human Sciences
The University of Western Australia
Crawley WA 6009
Australia
Country 122110 0
Australia
Phone 122110 0
+61407844746
Fax 122110 0
Email 122110 0
amanda.salis@uwa.edu.au
Contact person for public queries
Name 122111 0
Prof Amanda Salis
Address 122111 0
Building 444
Mailbag Delivery Point (MBDP) M408
School of Human Sciences
The University of Western Australia
Crawley WA 6009
Australia
Country 122111 0
Australia
Phone 122111 0
+61407844746
Fax 122111 0
Email 122111 0
amanda.salis@uwa.edu.au
Contact person for scientific queries
Name 122112 0
Prof Amanda Salis
Address 122112 0
Building 444
Mailbag Delivery Point (MBDP) M408
School of Human Sciences
The University of Western Australia
Crawley WA 6009
Australia
Country 122112 0
Australia
Phone 122112 0
+61407844746
Fax 122112 0
Email 122112 0
amanda.salis@uwa.edu.au

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
Yes
What data in particular will be shared?
Individual participant data underlying published results
When will data be available (start and end dates)?
Immediately following publication, available for 15 years after date of publication, or 15 years after conclusion of the project, whichever is later
Available to whom?
Only researchers who provide a methodologically sound proposal, decided on a case-by-case basis at the discretion of the Primary Investigator.
Available for what types of analyses?
Any purpose
How or where can data be obtained?
Access subject to approvals by Principal Investigator (amanda.salis@uwa.edu.au)


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.