Comparative Clinical Evaluation of Estrogenic Preparations by the Menopausal and Amenorrheal Indices*†

ESTROGENS for clinical use are usually standardized either by animal assay or by unit weight of crystalline material. Although such methods yield some information as to the expected comparative efficacy of these preparations in man they are inadequate for exact dosage relationships in clinical medicine. Hence, it is desirable that the relative activity of estrogens be based upon human ‘assay’ rather than biologic or chemical standardization procedures. The investigation of the clinical efficacy of different hormonal preparations, however, presents many difficulties and must, of necessity, entail large series of subjects to offset the inroads of biologic variation. Unfortunately, in the clinical evaluation of the effectiveness of steroid estrogens or their stilbene confreres, greater variability of response and less predictability of results occur than in animal assay procedures. In the latter assay methods one can adhere to a rigid selection of an adequate number of properly standardized subjects. The hor...