Overall aim:
This pilot trial aims to understand the feasibility and acceptability of the syd app. The
main focus is around the plant-based recipes and information pages delivered through the
chat functionality.
Specific objectives:
The primary objective is to understand the feasibility and acceptability of setting up
and running a trial with the syd app, focusing on the reach, adoption, implementation,
and maintenance. The secondary objectives are to explore the indicative efficacy of the
app in facilitating more sustainable and healthier diets, measured by a change in meat
and legume intake, to what extent the recipes and information pages contribute to this
effect, and whether there is a relationship between the self-perceived capabilities,
opportunities and motivations to consume a sustainable and healthier diet.
Intervention:
The overall aim of syd is to enhance general wellbeing across nine domains, through
completing activities and forming micro habits. The app has five main pages (Home, Daily
Plan, Journal, Profile, and Chat). Users can input a goal, browse the 'activity pages',
enter them into their daily plan, and complete them. When interacting with the app by
completing activities, conversing in the chat, journaling or through other methods, the
app calculates their 'life quality index' across all domains and presents this to users
in the profile page. As the app focuses on multiple health behaviours rather than dietary
change specifically, only some of the features are relevant to diet, mainly the 'activity
pages' that contain food-related information and recipes. The information pages contain
general information on certain aspects of diets for health and sustainability, quick tips
in achieving dietary goals, and more detailed information on "What", "Why" and "How" one
can adopt healthy dietary principles. The recipes are available for breakfast, lunch and
dinner, and vary in their composition of healthy and sustainable foods. The chat function
uses a large language model to converse and recommend content to users based on their
engagement in the app overall, as well as the prompts users input into the chat.
Sample size:
The target sample size will be 99 (33 per arm), which will account for the possibility of
40% dropout in the first two weeks, which is typical for smartphone apps, and would still
suffice the rule of thumb for 25 per group to be included in a pilot study to yield a
small standardised effect size.
Outcomes:
Outcomes (and data) that will be collected and include 1) programme reach (population
characteristics), 2) adoption of the app (participation and retention rates), 3)
acceptability of the intervention (engagement with and usefulness of the app features),
4) implementation of delivering the intervention (compliance), 5) maintenance of the
intervention (participant and organizational sustainability), and 6) efficacy of the
intervention (indications of change in behavioural determinants and behaviours).