Health4Me: text messaging to support adolescent physical and mental health and wellbeing in the community

Intervention group The intervention group (n=195) will receive a 6-month semi-personalised, two-way text message program and also have the opportunity to communicate by telephone or videoconference with an English-speaking university qualified health counsellor, trained in motivational interviewing over the 6-month intervention period. This study is completely virtual (online) and no in-person study visits are required. The text messages are designed to support and improve physical and mental health over the intervention period. Based on our preliminary work, text messages were drafted based on six priority areas, namely, physical activity, nutrition and food industry, body image, mental health, media and climate change. These text messages will be contextualised and refined in Phase 1 of the study (not a RCT, no registration available), examples are available in the published co-design paper: https://doi.org/10.1186/s40900-023-00524-4) Message frequency and timing Each intervention participant will receive a customised and semi-personalised set of text messages sent on 4-5 random days per week, including 1 day/weekend, and at random times. If the participant is attending high school, the weekday text messages will only be sent before or after school hours (8.00AM to 9.00AM or 3.30PM to 7.30 PM). The text messages will be semi-personalised by selecting context relevant to the participants characteristics such as dietary behaviours, age and education or work setting. Each message will have a unique signature as the study name to ensure that participants know these messages are from the research study and participants at enrolment will be told how to unsubscribe if required. Participants can also update their key information, for example, mobile phone number, change in dietary behaviours through the course of the study and this will be reflected in the ongoing text messages they receive. Messages are sent at no cost to the participants and a bulk-rate cost to the study. The intervention will encourage two-way communication via questions/polls in the text messages asking participants to respond. All replies and responses will be reviewed in regular weekly team meetings. Adherence to the intervention will be monitored through the text message delivery software - where we are able to view number of text messages sent, delivered, bounced and undelivered. Adherence will also be monitored in the process evaluation at the end of the intervention period. Role of the health counsellor Once a month (6 in total), intervention participants will be sent a text message encouraging them to call the university qualified health counsellor to ask questions or request additional information. The personalised health counselling calls will last 10-15 minutes and will be delivered according to standardized protocol. The university qualified health counsellor (allied health or public health professional) will monitor and respond to participants’ request for a call each month either via text message or phone call within 3 working days. Participants are allowed 6 health counselling calls in total over 6-months. The health counselling calls will allow participants to set behavioural goals, discuss barriers and enablers to behaviour change, and their overall progress. This part of the intervention is based on the evidence-based TEXTBITES Study (ACTRN12619000389101) for obesity prevention in adolescents.