Comparison of two 25-hydroxyvitamin D immunoassays to liquid chromatography-tandem mass spectrometry in assessing samples from the Chinese population

Although some systematic bias was found, the DiaSorin-RIA and IDS-EIA kits met the minimum performance goal for 25-OH-D measurement and can be recommended for routine use in the Chinese population. However, further studies are needed to assess 25-OH-D measurement immunoassays with lower bias and that are more suitable for the Chinese population.