The Role of Randomized Controlled Trials in Assessing the Benefits and Risks of Long-Term Hormone Replacement Therapy: Example of the Womenʼs Health Initiative

Observational studies suggest that hormone replacement therapy among postmenopausal women may have important benefits, particularly in relation to heart disease and bone fractures, but may also convey important risks, most notably for breast cancer. The magnitude of these potential benefits and risks and the prevalence of use of hormone replacement therapy in the United States make the question of benefits versus risks a very pressing public...