The diagnosis of hyperandrogenism is dependent on the accuracy and precision of measurement of the clinical features and the laboratory androgen assays. Hyperandrogenism in the context of polycystic ovary syndrome (PCOS) is a term used loosely to encompass both the clinical features of acne, hirsuties and androgenic alopecia and the laboratory evidence of hyperandrogenaemia. The relationship between acne and biochemical hyperandrogenaemia is well established but the number of women with acne in unselected populations is so great that it makes the link with PCOS unconvincing, particularly since the incidence of acne seems to be greater than that of PCOS. Anovulation is assessed by measuring the serum progesterone during the mid-luteal phase. Consecutive series of women with either a single symptom or various combinations of symptoms would be subjected to formal receiver operating characteristic (ROC) analysis to determine the optimal diagnostic characteristics.