A feasibility and pilot study into the use of a phone app to enhance a virtual Meal Replacement weight loss Program.

We will use a type 2 hybrid effectiveness implementation trial design. The study will be conducted at the Metabolism & Obesity Service, Royal Prince Alfred Hospital Sydney Australia, a tertiary weight loss clinic. The clinic runs seven meal replacement group programs throughout the calendar year. The program is called “Rapid Weight Loss” and is conducted virtually using Zoom via six sessions over 12 weeks. Each group will be randomly assigned to either an enhanced, including a specifically developed mobile app, or a standard arm. Six groups will be included in the study three of each type. Data will be collected during and at the end of the 12-week program and then at 6, 9 and at the end of 12 months. Patients who wish to attend the Rapid Weight Loss program, are allocated to the next available group after their referral to the clinic has been received. The Enhanced groups will be randomly assigned by pulling E (Enhanced Group) or S (Standard) cards out of a hat (3 of each group will be included). Session 1 of the 6 sessions explains the meal replacement program and in the Enhanced group it will also include an explanation of how to download and use the app My VLED. All information regarding the meal replacement program will be the same between the enhanced and control groups. The enhanced group will be encouraged to use the My VLED App to record weekly weight, biomarkers such blood glucose levels , and cholesterol markers (if known), blood pressure and monitor for symptoms. It will also provide information about the weight loss program. Participants will be required to provide their own smart phone. There will be no penalty to the participant if they don't have a smart phone. Although patients will be encouraged to download and use the app they will not have to show proof of doing so as the clinician can see if they have downloaded the app or not. Part of the study is to see the uptake of the app. All participants will be encouraged to ask questions during the online groups. The clinician will monitor the Enhanced group by checking the app dashboard and will be able to tailor information in the group sessions depending on the group’s progress. The Standard group will be asked to report their body weight each week to the clinician by email (current standard care). All participants are encouraged to get in contact if they have any questions or concerns. At the end of the 12 weeks all participants will be asked to complete a short survey to determine acceptability of the app and the Rapid Weight Loss program and what factors were favourable or hindering. Program retention (number of weeks between first and last session attended,) and engagement with the study (number of group sessions attended), app usage behaviour and adherence to self-monitoring will also be assessed. Clinicians will be asked each week to provide an estimate of the amount of time spent interacting with participants outside the delivery of the online program. The number of emails received from participants will also be recorded. At the end of the study clinicians will provide feedback on the acceptability of the My VLED app from the clinicians’ point of view. Weight and attendance data will be compared between the two groups to ensure Enhanced program is at least equivalent to standard care. Weight and attendance data will be monitored at 3, 6 and 12 months post intervention.