Proficiency Testing/EQA / 2024 Surveys / Endocrinology Help Please log in to determine if you are eligible to purchase PT Programs. 25-OH VITAMIN D, TOTAL - VITD Analytes/procedures in bold type are regulated for proficiency testing by the Centers for Medicare & Medicaid Services (CMS). Analyte Challenges per Shipment Number of Shipments 25-OH vitamin D, total 3 Two shipments per year Program Information Three 1.0‑mL liquid serum specimens Conventional and International System of Units (SI) reporting offered Shipping Schedule Shipment A: April 22 Shipment B: November 18 Guest Log in/Register Customers Who Bought This Item Also Bought ACCURACY-BASED VITAMIN D VIEW DETAILS > VITAMIN D CVL VIEW DETAILS >