Androgens like testosterone and DHT play a critical role in the pathogenesis of a number of dermatological conditions including acne , seborrhea , hirsutism (excessive facial/body hair growth in women), and pattern hair loss (androgenic alopecia).  In demonstration of this, women with complete androgen insensitivity syndrome (CAIS) do not produce sebum or develop acne and have little to no body , pubic , or axillary hair .   Moreover, men with congenital 5α-reductase type II deficiency , 5α-reductase being an enzyme that greatly potentiates the androgenic effects of testosterone in the skin, have little to no acne, scanty facial hair , reduced body hair, and reportedly no incidence of male pattern hair loss.      Conversely, hyperandrogenism in women, for instance due to PCOS or CAH , is commonly associated with acne and hirsutism as well as virilization (masculinization) in general.  In accordance with the preceding, antiandrogens have been found to be highly effective in the treatment of the aforementioned androgen-dependent skin and hair conditions.  
A system of standardizing the PT in oral anticoagulant control was introduced by the World Health Organization in 1983. It is based upon the determination of an International Normalized Ratio (INR) which provides a common basis for communication of PT results and interpretations of therapeutic ranges. The INR system of reporting is based on a logarithmic relationship between the PT ratios of the test and reference preparation. The INR is the PT ratio that would be obtained if the International Reference Preparation (IRP), which has an ISI of , was used to perform the test. Early clinical studies of oral anticoagulants, which formed the basis for recommended therapeutic ranges of to times control mean normal PT, used sensitive human brain thromboplastin. When using the less sensitive rabbit brain thromboplastins commonly employed in PT assays today, adjustments must be made to the targeted PT range that reflect this decrease in sensitivity.