The cost-effectiveness of a proportionate parenting programme for primary caregivers and their child: an economic evaluation using evidence from the E-SEE Trial

BACKGROUND: Behavioural and mental disorders have become a public health crisis; averting mental ill-health in early years can achieve significant longer-term health benefits and cost savings. This study assesses whether the Enhancing Social-Emotional Health and Wellbeing in the Early Years (E-SEE-Steps)—a proportionate universal delivery model comprising the Incredible Babies book (IY-B) and the Incredible Years Infant (IY-I) and Toddler (IY-T) parenting programmes is cost-effective compared to services as usual (SAU) for the primary caregiver, child and dyad. METHODS: Using UK data for 339 primary caregivers from the E-SEE trial, we conducted a within-trial economic evaluation assessing the cost-effectiveness of E-SEE Steps. Health outcomes were expressed in quality-adjusted life-years (QALY) and costs in UK pounds sterling (2018–19). Missing data were populated via multiple imputation and costs and QALYs discounted at 3.5% per annum. Cost-effectiveness results were conducted for primary caregivers, children and dyad using econometric modelling to control for patient co-variables. Uncertainty was explored through scenario and sensitivity analyses. RESULTS: The average cost of E-SEE Steps intervention was £458.50 per dyad. E-SEE Steps was associated with modest gains in primary caregiver HRQoL but minor decrements in child HRQoL compared to SAU. For primary caregivers, E-SEE Steps was more effective (0.034 QALYs) and more costly (£446) compared to SAU, with a corresponding incremental cost-effectiveness ratio (ICER) of £13,011 per QALY. In children, E-SEE Steps was strictly dominated with poorer outcomes (-0.005 QALYs) and greater costs (£178) relative to SAU. QALY gains in primary caregivers exceeded those QALY losses found in children, meaning E-SEE Steps was more effective (0.031 QALYs) and costly (£621) for the dyad (ICER: £20,062 per QALY). All scenario analyses found E-SEE Steps cost-effective for the dyad at a £30,000 per QALY threshold. Sensitivity analyses found significant cost reductions from expansions in programme delivery and attendance. CONCLUSIONS: E-SEE Steps achieved modest health gains in primary caregivers but small negative effects on children and was more costly than SAU. E-SEE Steps appears cost-effective for the dyad, but the results should be interpreted with caution given the potential detrimental impact on children. TRIAL REGISTRATION: ISRCTN11079129; Pre participant trial enrolment, 11/05/2015 SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12913-022-08220-x.