OBJECTIVES: Challenging behavior of children with intellectual disability is associated with increased healthcare, social, and societal costs. We assessed the incremental cost per Quality Adjusted Life Year (QALY) gained of level 4 Stepping Stones Triple P (SSTP) parenting intervention in addition to Treatment as Usual (TAU) delivered over 9 weeks in 261 pre-school children with moderate to severe intellectual disability using data from a multi-center, parallel group randomized controlled trial (EPICC-ID trial).

METHODS: For the healthcare system perspective, data was collected on use of health services in primary and community care, investigations and prescribed medication, hospital admission and outpatient attendance, ambulance use, and social care. For the analysis from the parent/caregiver perspective, we additionally collected data on out-of-pocket expenses.

The primary health economic outcome measure was QALYs derived from utility scores, obtained using the Pediatric Quality of Life Inventory™ (PedsQL™) General Core Scales (GCS). Mapped EQ-5D-Y utility scores algorithms were used to provide an empirical basis for estimating health utilities and form QALYs.

RESULTS: Parental group costs were significantly higher for the SSTP arm (adjusted mean difference=£38.97, p-value 0.013), whereas health visitor costs were significantly higher for the TAU arm (adjusted mean difference= £53.08, p-value 0.001).

Over 12 months, covering 10 months of cost data, the SSTP dominates TAU (mean cost difference of -£1,057.88 (95%CI -£3,218.6 to -£46.67) and mean QALY difference of 0.005 (95%CI -0.023 to 0.051)). The total cost of training in delivering the SSTP intervention was estimated at £26 per participant. At £30,000 willingness to pay for a QALY gained, there is 89% (healthcare perspective) and 71% (parent/caregiver perspective) probability that SSTP is cost-effective compared to TAU.

CONCLUSIONS: The addition of SSTP intervention to TAU for pre-school children with intellectual disability did generate statistically significant cost savings alongside a positive mean point estimate in HRQoL compared to TAU.