June 19, 2019 - For measurement of cortisol in peripheral blood, serum is the only acceptable sample type. In 2015 we transitioned our serum cortisol assay to a new method while maintaining our previous method for plasma samples. Effective July 8, 2019 we will no longer support that previous method and will not be able to measure cortisol on plasma samples. Moving forward, plasma will not be accepted for cortisol testing.

Our online test catalog will always have the current and correct specimen type, collection protocol, shipping requirements, and additional information. Please contact us with any questions or concerns.