Acceptability, engagement and exploratory outcomes and costs of a co-designed intervention to support children of parents with a mental illness: Mixed-methods evaluation and descriptive analysis.

Children whose parents have a mental illness are much more likely to experience mental health problems and other adverse long-term impacts. Child-centred psychosocial interventions can be effective, but not much is known about how to design and implement them in different settings. A pre-post, mixed methods, single-arm evaluation of a co-designed social support intervention with parents and children (4-18 years) measured parents' mental health (PHQ-9), perceived social support (ENRICHD), parental self-efficacy (PSAM) and children's mental health (SDQ), quality of life (Kidscreen-27), and child service use (CAMHSRI-EU) at baseline and 6 months. Qualitative data were gathered at 6 months to explore parents' and children's experience with the intervention. Twenty-nine parents and 21 children completed baseline and follow-up questionnaires; 22 parents and 17 children participated in interviews. Parents' depression (MD -1.36, SD 8.08), perceived social support (MD 1, SD 5.91), and children's mental health potentially improved, and children's service use and costs potentially reduced (€224.6 vs. €122.2, MD 112.4). Parental self-efficacy was potentially reduced (MD -0.11, SD 3.33). The sample was too small to perform statistical analysis. Favourable themes emerged describing the high satisfaction with the intervention, parents' improved understanding of the impact of their mental health problems on children, and improvements in parent-child relationships. This study contributes to an emerging evidence base for co-designed child-centred interventions to prevent the transgenerational transmission of poor mental health.