Febrile neutropenia (FN) represents one of the leading dose-limiting toxicities of cancer chemotherapy. The CSFs have been shown to reduce the incidence of FN in a variety of settings. Cost minimization models have established FN risk thresholds (FNRTs) for primary prophylaxis with the CSFs. OBJECTIVES: Determine the impact of CPMs on FNRT estimates with the CSFs. METHODS: Cost minimization models based on standard decision theory were generated incorporating probabilities and resource utilization from randomized clinical trials and unit cost information from local institutional sources. Sensitivity analyses were performed varying resource use, costs, and test performance characteristics. FNRTs were derived at which cost equivalence was reached in each model. The test performance of possible CPMs was assessed utilizing the likelihood ratio (LR) for discriminating high risk patients with probability prob(HR). RESULTS: Baseline cost minimization models were equated with CPMs with a LR=1.0. The FNRT for CSF use decreases as hospitalization length of stay (LOS) or cost/day increase. Any CPM associated with a LR+>1 generates lower FNRTs than under baseline conditions. Test efficiency of the CPMs improves with increasing LR+ with optimal performance observed between 2.0 and 4.0. In balanced CPMs with LR+=3.0, FNRTs are reached for costs/day of $1000, $1500 and $2000 at 0.21, 0.16, and 0.13 respectively. In unbalanced CPMs, FNRTs are <10% at prob(HR)= 0.4, 0.3, 0.2, and 0.1 at costs/day of $1700, $1000, $600 and $300 respectively. CONCLUSIONS: Efficient CPMs to identify high risk patients should be able to further reduce costs and FNRTs for CSF use based on cost minimization.