REACH-ASD: a UK randomised controlled trial of a new post-diagnostic psycho-education and acceptance and commitment therapy programme against treatment-as-usual for improving the mental health and adjustment of caregivers of children recently diagnosed with autism spectrum disorder

Autism is a neurodevelopmental disability affecting over 1% of UK children. The period following a child's autism diagnosis can present real challenges in adaptation for families. Twenty to 50% of caregivers show clinically significant levels of mental health need within the post-diagnostic period and on an ongoing basis. Best practice guidelines recommend timely post-diagnostic family support. Current provision is patchy, largely unevidenced, and a source of dissatisfaction for both families and professionals. There is a pressing need for an evidenced programme of post-diagnostic support focusing on caregiver mental health and adjustment, alongside autism psycho-education. This trial tests the clinical and cost-effectiveness of a new brief manualised psychosocial intervention designed to address this gap. This is a multi-centre two-parallel-group single (researcher)-blinded randomised controlled trial of the Empower-Autism programme plus treatment-as-usual versus usual local post-diagnostic offer plus treatment-as-usual. Caregivers of children aged 2-15 years with a recent autism diagnosis will be recruited from North West England NHS or local authority centres. Randomisation is individually by child, with one "index" caregiver per child, stratified by centre, using 2:1 randomisation ratio to assist recruitment and timely intervention. Empower-Autism is a group-based, manualised, post-diagnostic programme that combines autism psycho-education and psychotherapeutic components based on Acceptance and Commitment Therapy to support caregiver mental health, stress management and adjustment to their child's diagnosis. The comparator is any usual local group-based post-diagnostic psycho-education offer. Receipt of services will be specified through health economic data. caregiver mental health (General Health Questionnaire-30) at 52-week follow-up. key caregiver measures (wellbeing, self-efficacy, adjustment, autism knowledge) at 12-, 26- and 52-week follow-up and family and child outcomes (wellbeing and functioning) at 52-week endpoint. N=380 (approximately 253 intervention/127 treatment-as-usual). Primary analysis will follow intention-to-treat principles using linear mixed models with random intercepts for group membership and repeated measures. Cost-effectiveness acceptability analyses will be over 52 weeks, with decision modelling to extrapolate to longer time periods. If effective, this new approach will fill a key gap in the provision of evidence-based ca