Imperial Collage Healthcare
17 November

Assay change for female testosterone

From 1st December 2014, the method for female testosterone analysis will change to immunoassay. This change is due to a reformulation of the assay by Abbott (the manufacturer of the kit) and the new method has improved sensitivity for the measurement of low level testosterone concentrations in females. Performance of this assay in the UKNEQAS external quality assurance scheme shows comparability to LC-MS/MS analysis. Moving to a fully automated method will result in faster turn around times for this test.

The reference ranges for both the immunoassay and the LC-MS/MS will be harmonised to derived values published in the literature1,2 and the new reference interval will be ≤ 2.0 nmol/L. Samples with elevated results on the immunoassay method will be automatically reflexed for confirmation by LC-MS/MS analysis.

Specimen type is serum and gel tubes are acceptable.

Samples received from external laboratories will continue to be analysed by LC-MS/MS first line; please request TesX to ensure the correct test is requested at booking in.

 For further information or queries please contact Emma Walker, Consultant Clinical Scientist


  1.  Clin Chem 2010;56:1138-47.
  2.  J Clin Endocrinol Metab 2013;98:3058-67.

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