Cost-Effectiveness of Assigning Early Interventions to Infants at High Risk for Autism Spectrum Disorder Using MRI Screening

OBJECTIVES: Using magnetic resonance imaging (MRI) to screen infant siblings of children with autism spectrum disorder (ASD) has been shown to be cost-effective, however, it is unknown which ASD interventions are most cost-effective. This study sought to investigate the cost-effectiveness of MRI screening strategies when paired with one of two ASD interventions; the Early Start Denver Model (ESDM) and Pivotal Response Treatment (PRT).

METHODS: A decision tree combined with a two state Markov model was developed in TreeAge to model costs and utilities of at risk 4-year-old children over a child’s lifetime. Four screening strategies were developed (treating all siblings, MRI screening at 6 months, at 12 months, and no MRI screening) for both the ESDM and PRT interventions resulting in eight unique strategies. Model inputs were obtained from trials testing MRI screening and clinical trials investigating ESDM and PRT using the Vineland Adaptive Behavior Scale (VABS) as intermediate endpoints. Societal, healthcare, and educational perspectives were adopted and discounted at 3%. The two state Markov model with an annual cycle length was run for 96 cycles. One way and probabilistic sensitivity analyses were performed.

RESULTS: Treating all with ESDM was most effective (28.08 QALYs) strategy and the least effective was status quo using PRT (27.66 QALYs). Using a societal perspective, all the strategies involving PRT were dominated by the treat all ESDM strategy in the base case analysis and MRI screening at 6 months with ESDM was the preferred strategy at a WTP threshold of 100,000/QALY. The probabilistic sensitivity analysis showed that MRI screening at 6 months with ESDM was the optimal strategy 4.00% of time at the WTP threshold.

CONCLUSIONS: This analysis found that using MRI screening to assign treatment for high-risk infant siblings of children diagnosed with ASD is cost effective when using an ESDM intervention.