I would be interested to hear if anyone uses calculated free testosterone by the Vermeulen equation with SHBG measured by Immulite 2000 and testosterone by Centaur. If so I would be interested in knowing what ref range you use. We use a range of 245 - 785 pmol/L Geoff Beckett Dr G J Beckett PhD FRCPath Room S6309 Clinical Biochemistry The Royal Infirmary of Edinburgh 51 Little France Crescent Little France Edinburgh EH16 4SA Tel 44 (0) 131 242 6868 Fax 44 (0) 131 242 6812 [log in to unmask] ------ACB discussion List Information-------- This is an open discussion list for the academic and clinical community working in clinical biochemistry. Please note, archived messages are public and can be viewed via the internet. Views expressed are those of the individual and they are responsible for all message content. ACB Web Site http://www.acb.org.uk List Archives http://www.jiscmail.ac.uk/lists/ACB-CLIN-CHEM-GEN.html List Instructions (How to leave etc.) http://www.jiscmail.ac.uk/