The results showed about 2-5 fold elevation of GAGs levels compared with those in normal control, and these levels decreased in ERTtreated MPS patients, suggesting this method is available for biomarker for monitoring ERT as well as NBS. Unexpectedly, KS levels were elevated in all MPS types. Conclusion: Method for early detection of patients with MPSs has established. Pilot NBS study is now under planning. Background: Newborn screening prompts early detection of infantile-onset Pompe disease and allows initiation of enzyme replacement therapy (ERT) before irreversible muscle damage. The incidence of infantile-onset Pompe disease is around 1 in 50 000 in Taiwan. Starting from 2009, newborns could be screened for Pompe disease on a self-paid basis. Recently the government is considering including Pompe disease as one of the universal newborn screening items. Therefore the purpose of this study was to conduct an economic evaluation of different screening strategies from the societal perspective. Study design: We used the modeling technique to perform a costeffectiveness analysis comparing two screening strategies, namely universal screening and self-paid screening. Results: Since over 90% of parents joined the screening program now on voluntary basis, from the point view of the society, a universal screening program would save USD$133 for every quality-adjusted life-year saved.