CD4 and Central hypothyroidism: Lastly, the criterion for screening (TSH >40 μU/ml) is the standard criterion used by the Taiwan government; however, recent reports suggest that use of multiple tests (ie, T4 and TSH) improves detection of primary and central hypothyroidism.27–29 Therefore, the screening program is improving every year, and detailed screening is performed to decrease misclassification of possible newborns.