^At androgen receptors; measured in human prostate tissue.
^Relative to Metribolone, which is by definition 100%
^Ayub M, Levell MJ (August 1989). "The effect of ketoconazole related imidazole drugs and antiandrogens on [3H] R 1881 binding to the prostatic androgen receptor and [3H]5 alpha-dihydrotestosterone and [3H]cortisol binding to plasma proteins". J. Steroid Biochem. 33 (2): 251–5. doi:10.1016/0022-4731(89)90301-4. PMID2788775.