Comparison of eight routine unpublished LC-MS/MS methods for the simultaneous measurement of testosterone and androstenedione in serum.

•8 routine unpublished LC-MS/MS methods for the simultaneous measurement of testosterone and androstenedione were compared.•Some of the investigated methods in the present study showed a good agreement.•There are differences in standardization between some of the assays and some assays show a high variation or low recoveries.•The overall agreement of unpublished routine methods compare unfavourably to the variation found in published methods.•These findings stress the importance of thorough initial validation but also for the continuous monitoring of LC-MS/MS methods.•The policy to require the use of LC-MS/MS assays alone is not an assurance for high quality sex steroid measurement results.