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Trial registered on ANZCTR


Registration number
ACTRN12620001288910p
Ethics application status
Submitted, not yet approved
Date submitted
2/10/2020
Date registered
30/11/2020
Date last updated
30/11/2020
Date data sharing statement initially provided
30/11/2020
Type of registration
Prospectively registered

Titles & IDs
Public title
Understanding how Australian adults choose and follow very low calorie diet (VLCD) programs, their food and eating behaviours, and associated effects on self-perceived physical and mental health
Scientific title
Understanding how Australian adults choose and follow very low calorie diet (VLCD) programs, their food and eating behaviours, and associated effects on self-perceived physical and mental health
Secondary ID [1] 302119 0
None
Universal Trial Number (UTN)
Trial acronym
OPTIFAST RWE Study: Phase 2
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Obesity 318783 0
Mental health 318784 0
Self-efficacy 318785 0
Eating behaviours 318787 0
Quality of life 318799 0
Condition category
Condition code
Diet and Nutrition 316800 316800 0 0
Obesity
Mental Health 316801 316801 0 0
Studies of normal psychology, cognitive function and behaviour

Intervention/exposure
Study type
Observational
Patient registry
False
Target follow-up duration
Target follow-up type
Description of intervention(s) / exposure
Two groups of participants will be recruited:
• Group 1: Participants who have used the OPTIFAST VLCD Program within the last 4 weeks, daily for 7 or more days in a row but do not meet the eligibility criteria for Group 2. Participants in this group will not answer all survey questions.
• Group 2: Participants who have used the OPTIFAST VLCD Program more than a month, at least daily for 4 or more days/week and either continue to use or ceased use within the last 4 weeks.
Participation involves completion of a once-off online survey. The online survey involves multiple components including:
- Demographic questionnaire
- OPTIFAST VLCD program use questionnaire
- Phyiscal activity questionnaire
- Health-related quality of life questionnaire
- Weight-related quality of life questionnaire
- Eating behaviours questionnaire
- Mental health questionnaire
- Self-efficacy questionnaire
They survey, including all questionnaires within the survey, will take 20 to 30 minutes in total to complete.

Convenience and snowball sampling will be used to recruitment participants via an advertisement platform including: QR Codes on flyers placed in pharmacies, advertisement with electornic links to the survey on the OPTIFAST Website, social media (private posts and paid posts), and websites/electronic networks of health care professionals.

At the completion of the questionnaire, if any responses indicate the participant may be using OPTIFAST unsafely, e.g. if they have a low BMI or are experiencing side-effects, they will recieve a message at teh end of the survey recommending they speak to their GP about their use of the OPTIFAST program. Participants will not be emailed a copy of their responses.
Intervention code [1] 318422 0
Not applicable
Comparator / control treatment
No control group
Control group
Uncontrolled

Outcomes
Primary outcome [1] 324917 0
Primary outcome 1: Self-reported weight loss (study-specific online questionnaire)
Timepoint [1] 324917 0
Timepoint: T1 online questionnaire (single timepoint during the once-off survey completion)
Secondary outcome [1] 386182 0
Secondary outcome 1: Quality of life assessed using EQ-5D-5L
Timepoint [1] 386182 0
Timepoint: T1 online questionnaire (single timepoint during the once-off survey completion)
Secondary outcome [2] 386183 0
Secondary outcome 2: Eating behaviours assessed using the Three-factor Eating questionnaire (TFEQ)
Timepoint [2] 386183 0
Timepoint: T1 online questionnaire (single timepoint during the once-off survey completion)
Secondary outcome [3] 386184 0
Secondary outcome 3: Physical activity assessed using the Global Physical Activity questionnaire (GPAQ)
Timepoint [3] 386184 0
Timepoint: T1 online questionnaire (single timepoint during the once-off survey completion)
Secondary outcome [4] 386185 0
Secondary outcome 4: Mental health assessed using Depression, Anxiety Stress Scale (DASS) questionnaire
Timepoint [4] 386185 0
Timepoint: T1 online questionnaire (single timepoint during the once-off survey completion)
Secondary outcome [5] 386186 0
Secondary outcome 5: Self-efficacy assessed using General Self-Efficacy (GSE) questionnaire and Nutrition and Physical Activity Self-Efficacy questionnaires (a composite survey with two domains - a) general and b) nutrition and physical activity)
Timepoint [5] 386186 0
Timepoint: T1 online questionnaire (single timepoint during the once-off survey completion)
Secondary outcome [6] 386188 0
Secondary outcome 6: Weight-related quality of life assessed using IWQoL-Lite
Timepoint [6] 386188 0
Timepoint: T1 online questionnaire (single timepoint during the once-off survey completion)
Secondary outcome [7] 386189 0
Secondary outcome 7: Facilitators and barriers to program adherence (study specific questionnaire)
Timepoint [7] 386189 0
Timepoint: T1 online questionnaire (single timepoint during the once-off survey completion)

Eligibility
Key inclusion criteria
- Aged 18-65yrs
- Currently residing in Australia
- Currently using or have used OPTIFAST VLCD at least once in the last 4 weeks
(i.e. must have consumed an OPTIFAST VLCD product at least once daily for 7 consecutive days within the last 4 weeks then subsequently ended program use OR must have consumed an OPTIFAST VLCD product at least once a day for 5 days in a week for 4 weeks and either continue use or ceased use within the last 4 weeks).
Minimum age
18 Years
Maximum age
65 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
- Cannot understand written English
- Pregnant women

Study design
Purpose
Psychosocial
Duration
Cross-sectional
Selection
Defined population
Timing
Prospective
Statistical methods / analysis
De-identified data will be analysed using a statistical package SPSS, SAS, or STATA. Descriptive statistics will be used to describe data collected from the screening component of the questionnaire (mean ± standard deviation, or frequency and percentage).

OPTIFAST VLCD users will be grouped by inductively-defined VLCD product usage patterns. Descriptive statistics will be performed and t-tests comparing groups. General linear models adjusted for factors including age, sex and BMI, ANOVA tables and chi-square tests for independence will be used to show relationships between variables. Post-hoc comparisons with Bonferroni adjustment will be used to investigate pairwise significance between categories of users.

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
ACT,NSW,NT,QLD,SA,TAS,WA,VIC

Funding & Sponsors
Funding source category [1] 306545 0
Commercial sector/Industry
Name [1] 306545 0
Nestlé Australia
Country [1] 306545 0
Australia
Primary sponsor type
Commercial sector/Industry
Name
Nestlé Australia
Address
CN of Building D, 1 Homebush Bay Drive, Rhodes, New South Wales 2138
Country
Australia
Secondary sponsor category [1] 307097 0
None
Name [1] 307097 0
None
Address [1] 307097 0
Country [1] 307097 0

Ethics approval
Ethics application status
Submitted, not yet approved
Ethics committee name [1] 306737 0
Bellberry Human Research Ethics Committee
Ethics committee address [1] 306737 0
123 Glen Osmond Rd, Eastwood SA 5063
Ethics committee country [1] 306737 0
Australia
Date submitted for ethics approval [1] 306737 0
14/10/2020
Approval date [1] 306737 0
Ethics approval number [1] 306737 0

Summary
Brief summary
Sixty-six percent of the Australian adult population are overweight or obese. Recently, there has been growing interest in very-low-calorie diets (VLCDs) for weight loss, due to greater long-term weight loss success and being more tolerable than conventional weight loss programs.
This nationwide cross-sectional survey aims to understand how Australian adults choose and follow very low calorie diet (VLCD) programs, their food and eating behaviours, and associated effects on self-perceived physical and mental health.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 104846 0
Dr Flavia Fayet-Moore
Address 104846 0
Nutrition Research Australia, Level 10, 20 Martin Place, Sydney NSW 2000
Country 104846 0
Australia
Phone 104846 0
+610286673200
Fax 104846 0
Email 104846 0
Contact person for public queries
Name 104847 0
Dr Flavia Fayet-Moore
Address 104847 0
Nutrition Research Australia, Level 10, 20 Martin Place, Sydney NSW 2000
Country 104847 0
Australia
Phone 104847 0
+610286673200
Fax 104847 0
Email 104847 0
Contact person for scientific queries
Name 104848 0
Dr Skye Marshall
Address 104848 0
Nutrition Research Australia, Level 10, 20 Martin Place, Sydney NSW 2000
Country 104848 0
Australia
Phone 104848 0
+610286673200
Fax 104848 0
Email 104848 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
To protect participant privacy, IPD will not be available.


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
SourceTitleYear of PublicationDOI
EmbaseReal world evidence on the characteristics of regular and intermittent users of a very-low calorie diet program and associations with measures of program success, health, and quality of life.2024https://dx.doi.org/10.1002/osp4.712
N.B. These documents automatically identified may not have been verified by the study sponsor.