Usability and preliminary efficacy of the youngsters upbringing mental health information and counselling app (YOUCA) for parents of children with mental health issues: study protocol for a mixed-methods randomised waitlist-controlled pilot trial

Introduction: Mental health problems among children and adolescents are increasing, while access to psychosocial and mental health care in Austria remains limited. Parents play a key role in recognising mental health concerns and initiating help-seeking, but may experience uncertainty, low self-efficacy, stigma-related barriers, and difficulties in identifying appropriate support. The Youngsters Upbringing Mental Health Information and Counselling App (YOUCA) was developed to provide parents with accessible information and practical guidance. This study will evaluate its usability, usefulness and acceptance using a mixed-method approach, as well as to provide preliminary estimates of intervention effects and outcome variability to inform the design of a future larger-scale randomised trial. Additionally, trial feasibility will be assessed. Methods and analysis: This mixed-methods randomised waitlist-controlled pilot trial uses a delayed intervention onset design. Twenty-five parents of children and adolescents aged 10 to 17 years will be recruited, with approximately 20 expected to be analysed. Participants will be randomised to immediate app access or a waitlist control group. App use lasts four weeks. Assessments will occur at baseline and immediately after app use, with an additional pre-intervention assessment in the waitlist group. Quantitative outcomes include perceived usability, parental concordance with preventive parenting practices, parental self-efficacy, and parenting-related self-regulation. Trial feasibility will additionally be assessed based on recruitment, retention, adherence to app use, completion of scheduled assessments, and documented technical or procedural issues. Qualitative interviews, an expert focus group, and usage diary data will complement the quantitative data. Quantitative outcomes will be analysed descriptively and exploratively, with effect estimates and 95% confidence intervals reported where appropriate. Qualitative data will undergo qualitative content analysis and be integrated with quantitative findings.