Bots, Michiel L The Osteoporosis Prevention and Arterial effects of tiboLone (OPAL) study: design and baseline characteristics. [electronic resource] - Controlled clinical trials Dec 2003 - 752-75 p. digital Publication Type: Clinical Trial; Journal Article; Randomized Controlled Trial; Research Support, Non-U.S. Gov't ISSN: 0197-2456 Standard No.: 10.1016/s0197-2456(03)00096-5 doi Subjects--Topical Terms: AgedBone Density--drug effectsCarotid Arteries--diagnostic imagingDisease ProgressionDouble-Blind MethodEstrogens, Conjugated (USP)--pharmacologyFemaleHumansMiddle AgedNorpregnenes--pharmacologyOsteoporosis--pathologyPostmenopause--drug effectsRandom AllocationRandomized Controlled Trials as Topic--methodsSurveys and QuestionnairesUltrasonography