Consumer Reports doesn't test drugs in its labs the way we test, say, computers and appliances. Instead, we work closely with experts like those at the Drug Effectiveness Review Project (DERP), which is based at the Oregon Health and Science University in Portland. DERP assigns teams of doctors at university-based research centers to examine hundreds, and sometimes thousands, of studies on a particular class or group of medicines. It then issues a report comparing the effectiveness, safety and best uses for the drugs.

The problem is that these reports are filled with dense medical language and can run hundreds of pages in length. So we translate the DERP findings, and those of other experts, into everyday language. We also choose Best Buys. These drugs are picked because we think they will deliver the best results, be the safest, and give most consumers the best value for their health care dollar.

DERP and Best Buy Drugs are part of a movement towards "evidence-based medicine." Advocates of evidence-based medicine try to get doctors and patients to base treatment decisions on independent and unbiased scientific evidence—not on personal preference or hunch. So the advice you'll find in this magazine represents our best judgment, and that of the experts we consulted, given the medical evidence available today. For more information on our methods, go to ConsumerReportsHealth.org/bbd.

We hope you'll find this advice useful. But it's not meant to replace your doctor's judgment as to your medical needs. Ultimately, decisions about your treatment can only be made on an individual basis, taking into account your health, medical history, and the other drugs you take. So use this guide to help you talk with your doctor, not as a substitute for his or her advice.