Economic evaluation of potential national childhood screening strategies for type 1 diabetes in Australia.

Background: Type 1 diabetes (T1D) is an autoimmune condition affecting children. We aimed to investigate the costs and cost-effectiveness of potential national childhood screening strategies for T1D compared to no screening (usual care). Methods: Screening costs were obtained from trial-based estimates. A Markov microsimulation model was developed to identify the most cost-effective childhood T1D screening strategy. The three screening strategies modelled were: Strategy 1) newborn genetic risk-stratification with bloodspot sampling, followed by autoantibody screening in at-risk children; Strategy 2) infant genetic risk-stratification using saliva sampling, followed by autoantibody screening in at-risk children; Strategy 3) population-wide autoantibody screening at two childhood ages. The model tracked 100,000 individuals from birth to 30 years of age. One-way and probabilistic sensitivity analyses were conducted. Findings: Newborn bloodspot genetic risk-stratified screening (strategy 1) was the most cost-effective strategy. Incremental cost-effectiveness ratios (ICERs) were $50,682 per quality-adjusted life year (QALY) gained for strategy 1, $85,440 per QALY gained for strategy 2, and $133,285 per QALY gained for strategy 3. In the optimal strategy (strategy 1), the cost was $480,798 per screen-detected T1D and $12,183 per episode of diabetic ketoacidosis avoided. Results were sensitive to changes in time horizon, discount rates, and cost of the screening tests. Interpretation: Of the three modelled T1D screening strategies, newborn bloodspot genetic risk-stratified screening was the most cost-effective. Varying cost inputs may change this hierarchy. Our economic evaluation will be useful for informing future T1D childhood screening policy in Australia and other high-income countries. Funding: JDRF Australia.