HoSt/VDSCP: Reference Measurements Services

The CDC Hormone Standardization Program and the Vitamin D Reference Laboratory provide measurement services to assign values to serum and other materials used for calibration and calibration verification. The program also helps laboratories using lab-developed tests and helps assay manufacturers with technical questions that help improve assay performance.

As part of these efforts, the CDC collaborates with providers of proficiency testing programs and external quality assurance programs that inform laboratories about the accuracy of their measurements. To assist clinical laboratories in assessing the accuracy of their measurements and to assist in identifying potential problems, the Hormone Standardization Program assigns values for accuracy-based surveys and regular proficiency testing surveys. Supplying reference measurements to survey providers allows providers to get critical information to their survey participants.

Laboratories are interested in more than just fulfilling the regulatory requirements of proficiency testing programs and earning a passing score. They would like to produce accurate results so patient data can be compared against clinical decision points and generally defined reference ranges. But while these accuracy-based surveys provide a convenient way for laboratories to assess their calibration and obtain initial information about possible problems with their assays, participation in such surveys does not replace programs such as HoSt and VDSCP.

The CDC Hormone Standardization Program and Vitamin D Reference Laboratory are currently collaborating with the following survey providers:

  • College of American Pathologist (CAP)
  • NY State Department of Health
  • Canadian External Quality Assessment Laboratory (CEQAL)

If you are interested in reference measurement services by the CDC Hormone Standardization Program or the Vitmain D Reference Laboratory, please complete the CDC Standardization Program Information Request Form pdf icon[PDF – 335 KB] and return it to

Page last reviewed: July 6, 2017