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Trial registered on ANZCTR

Registration number
Ethics application status
Date submitted
Date registered
Date last updated
Date data sharing statement initially provided
Type of registration
Prospectively registered

Titles & IDs
Public title
Design of a Theory-based Mobile Health Coaching App for Surgery in Obese Patients: A Study Protocol
Scientific title
User-centred Design of a Theory-based, Ontology-driven Mobile Health Coaching App for Fitness before Surgery in Obese Patients: A Study Protocol
Secondary ID [1] 300785 0
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
obesity 316647 0
diet and nutrition 316716 0
Condition category
Condition code
Surgery 314891 314891 0 0
Other surgery
Diet and Nutrition 315065 315065 0 0

Study type
Description of intervention(s) / exposure
Material: A mobile app will be developed to provide multi-disciplinary health coaching
Procedure: Patients will log on to the app, complete a questionnaire to describe their current health status. The app will direct them to health resources, send them 4 coaching notifications a week, and will track their progress towards their self-nominated goals. Participants will be able to use the app as often as they wish.
Delivery: automatically via the mobile phone app
Duration: the study will cease at 6 months, or earlier if a person has their scheduled surgery before 6 months
Location: in participants' own time and space
Content: examples of coaching notifications include:
Diet: "Make sure you eat a rainbow of different colours of fruit and vegetables to reach your nutrition needs", "Cutting down your food proportions slowly over time will create long term changes"
Exercise: "Walking for 30 minutes a day improves heart and lung health", "Aim to increase your daily step count by 500 steps this week"
Psychology: "By making repeated small changes in habits, most people can reach their goals. You can too", " All of us can do with a little support from time to time. Do you know that you can talk to your GP about your mental well being?"
Medical: "Need some extra help reaching your goals this week? Contact NSW Get Healthy on xxxxx for free lifestyle coaching'
Intervention code [1] 317107 0
Treatment: Other
Comparator / control treatment
no control group, as this first trial is a pilot study
Control group

Primary outcome [1] 323213 0
change in weight

All outcomes will be self-reported as entered into the app
Timepoint [1] 323213 0
For each participant, the study will end 6 months after enrolment or at the time of surgery, whichever happens first.
Secondary outcome [1] 381188 0
Change in physical activity using the International Physical Activity Questionnaire
Timepoint [1] 381188 0
For each participant, the study will end 6 months after enrolment or at the time of surgery, whichever happens first.
Secondary outcome [2] 381379 0
Change in nutrition, using the Australian Bureau of Statistics, Australian Health Survey short questions
Timepoint [2] 381379 0
For each participant, the study will end 6 months after enrolment or at the time of surgery, whichever happens first.
Secondary outcome [3] 381380 0
Change in health engagement, using the Patient Activation Measure
Timepoint [3] 381380 0
For each participant, the study will end 6 months after enrolment or at the time of surgery, whichever happens first.

Key inclusion criteria
Age >=18yr, body mass index >= 30 kg/m2, booking for elective surgery with a Category C (up to 12 months) waiting period
Minimum age
18 Years
Maximum age
90 Years
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
not having a smartphone, difficulties understanding English

Study design
Purpose of the study
Educational / counselling / training
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?

Intervention assignment
Single group
Other design features
Not Applicable
Type of endpoint(s)
Statistical methods / analysis
This is a pilot study. Our sample size will be based on convenience, with approximately 50-100 patients. Statistics will be mainly descriptive. Changes at the end of the study will be compared to baseline measures from the beginning of the study using t-tests with continuous parametric data, and ordinal measures for non-parametric data.

Recruitment status
Not yet recruiting
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)
Recruitment hospital [1] 16114 0
Wollongong Hospital - Wollongong
Recruitment postcode(s) [1] 29632 0
2500 - Wollongong

Funding & Sponsors
Funding source category [1] 305243 0
Name [1] 305243 0
University of Wollongong, Illawarra Health and Medical Research Institute
Address [1] 305243 0
Northfields Avenue, Wollongong, NSW 2500
Country [1] 305243 0
Primary sponsor type
Dr Natalie Smith
c/o Wollongong Hospital, Crown St, Wollongong. NSW 2500
Secondary sponsor category [1] 305599 0
Name [1] 305599 0
Address [1] 305599 0
Country [1] 305599 0

Ethics approval
Ethics application status
Ethics committee name [1] 305586 0
UOW and ISLHD Health and Medical Human Research Comittee
Ethics committee address [1] 305586 0
University of Wollongong, Northfields Ave, Wollongong. NSW, 2500
Ethics committee country [1] 305586 0
Date submitted for ethics approval [1] 305586 0
Approval date [1] 305586 0
Ethics approval number [1] 305586 0

Brief summary
Obesity is the leading public health challenge in Australia. Approximately 3,300 patients who undergo elective surgery in the Illawarra and Shoalhaven Local Health District each year are obese.. This area does not currently offer a comprehensive multi-disciplinary weight management clinic.

The waiting time for many patients with obesity booked for common operations is three months or longer. Losing weight and increasing cardio-respiratory fitness can improve aerobic capacity and physiological reserve.

The majority of people routinely carry a ‘smart’ mobile phone. We will design, build, pilot, and evaluate a mobile application to provide patient-centered interactive health coaching specifically designed for patients with obesity who are waiting for surgery.

Our hypothesis is that mobile health coaching via an app utilising the time that patients with obesity spend on surgical waiting lists will improve their health, fitness, and motivation at the time of operation.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 100866 0
Dr Natalie Smith
Address 100866 0
Dept Anaesthesia, Wollongong Hospital, Crown St, Wollongong, NSW 2500
Country 100866 0
Phone 100866 0
+61 0439473790
Fax 100866 0
Email 100866 0
Contact person for public queries
Name 100867 0
Dr Natalie Smith
Address 100867 0
Dept Anaesthesia, Wollongong Hospital, Crown St, Wollongong, NSW 2500
Country 100867 0
Phone 100867 0
+61 0439473790
Fax 100867 0
Email 100867 0
Contact person for scientific queries
Name 100868 0
Dr Natalie Smith
Address 100868 0
Dept Anaesthesia, Wollongong Hospital, Crown St, Wollongong, NSW 2500
Country 100868 0
Phone 100868 0
+61 0439473790
Fax 100868 0
Email 100868 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No/undecided IPD sharing reason/comment
Patient information will be collected individually, but kept anonymous for analysis and study purposes
What supporting documents are/will be available?
Study protocol
How or where can supporting documents be obtained?
Type [1] 7349 0
Study protocol
Citation [1] 7349 0
Link [1] 7349 0
Email [1] 7349 0
Other [1] 7349 0
Summary results
No Results