Developmental regression is when children lose one or more skills they have established. Families caring for these children need timely recognition to assist diagnosis and tailored interventions. Families also need support to develop practical skills for caregiving and strategies to promote family well-being and community participation. Given the high caring demands, flexibly delivered approaches are needed to accommodate family routines. Online delivery of health-related interventions that provide coaching, information, or both has been found to be a feasible and effective option for families. Family Focus is a new family-centred online programme, co-designed with parents and family advocates, clinicians, and researchers to support and empower primary carers.

This study is a prospective, pragmatic randomised controlled trial comparing the effectiveness of online parent coaching plus Family Focus (Coaching+FF) to Family Focus alone (FF) for primary carers of children experiencing developmental regression. A sample of 56 families will be randomised in a 1:1 ratio. Outcomes are assessed at baseline, post-intervention and 12-month post-randomisation. The primary outcome is parental stress symptoms at post-intervention. Secondary outcomes include parental depressive and anxiety symptoms, parental engagement in health-promoting activities, family empowerment, family quality of life and child global health outcomes. The study will also examine the uptake and acceptability of specific coaching and FF components and explore the facilitators and barriers to their delivery and implementation.

Ethics approvals were obtained from the participating organisations (Monash Health HREC/107806). Informed consent is obtained from parents/guardians of children prior to study enrolment. Study findings will be disseminated through peer-reviewed publications, conference presentations and lived experience agencies.

ISRCTN25513446.