OBJECTIVES: Typical cost-effectiveness studies of CSII therapy focus on long-term health-economic outcomes, with little emphasis on immediate clinical and economic benefits which underpin long-term complication-related savings. The objective was therefore to evaluate the short-term health-economic outcomes of CSII versus multiple daily injections (MDI), using best practice modelling methodology with a focus on changes in glycosylated haemoglobin (HbA1c), severe hypoglycemic events (SHE), insulin consumption and complication and insulin related (CIR) costs. METHODS: The SWITCH costing model was developed based on regression equations for changes in HbA1cand SHE. Model inputs were derived from best available evidence. Analysis was performed from a healthcare payer’s perspective for the Netherlands. Model outputs included clinical benefits and potential reductions in CIR costs. Sensitivity analysis determined the robustness of the results. RESULTS: In a cohort representative of Netherlands, switching patients with poorly controlled HbA1c on MDI [average HbA1c 9%; 0.2 SHE per patient year (PPY)] to CSII results in the following calculated improvements PPY: 50% SHE potentially avoided [€65 expenditure reduction (ER)], insulin dose reduction of 7,597 IU [€141 ER]; and a relative HbA1c reduction of 12% [€406 ER]. The total calculated short-term improvement in this subgroup is associated with potential savings in CIR cost of €612 PPY. Similarly, switching patients with frequent SHE on MDI [average HbA1c 7%; 1.0 SHE PPY] to CSII results in the following calculated improvements PPY: 80% SHE potentially avoided [€523 ER], insulin dose reduction of 3,799 IU PPY [€71 ER]; and a relative HbA1c reduction of 1% [€10 ER]. The total calculated short-term improvement in this subgroup is associated with potential savings in CIR cost of €603 PPY. CONCLUSIONS: In addition to long-term benefits; depending on baseline values, switching patients from MDI to CSII potentially results in improved clinical outcomes with significant reductions in short-term CIR costs.