OHSU Researchers Provide Evidence for National Medical Recommendations

04/17/01    Portland, Ore.

Evidence-based studies are basis for preventive health guidelines

The third U.S. Preventive Services Task Force (USPSTF) today issued its recommendations for primary care clinicians on four medical conditions, three of which were based on systematic reviews of medical literature by researchers at Oregon Health Sciences University.

The task force is a panel of independent, private-sector experts in prevention and primary care that conducts impartial assessments of scientific evidence for a broad range of clinical conditions to produce recommendations for primary care clinicians about every five years. Through the Agency for Healthcare Research and Quality, the group works with two institutions that review new research on the clinical and scientific data published since its last recommendations so that it can update its guidelines.

"This is a huge undertaking for a research program and the reward of being involved in improving preventive health care nationwide is enormous," said Mark Helfand, M.D., M.S., director of the OHSU Evidence-Based Practice Center, and co-author on three of the four reviews on which the recommendations were based. The other institution conducting studies for the panel is the Research Triangle Institute-University of North Carolina Evidence-Based Practice Center.

In one recommendation, the USPSTF urges doctors to screen all sexually active women ages 25 and younger, as well as older women at risk for chlamydia, as part of regular health care visits. Chlamydia is the most common bacterial sexually transmitted disease in the country, with an estimated 3 million new cases each year. Most women have no symptoms when initially infected, but if not treated, can develop pelvic inflammatory disease, infertility and other serious health problems, including increased risk of HIV infection.

The study on chlamydia screening was authored by Heidi D. Nelson, M.D., M.P.H., professor of medicine and medical informatics and outcomes research in the OHSU School of Medicine, and Helfand. They analyzed dozens of scientific and medical articles on the subject to cull the most relevant and conclusive results.

In addition, the USPSTF released recommendations on screening for skin cancer and bacterial vaginosis in pregnancy. There is still insufficient scientific evidence to determine whether regular, total body skin examination for skin cancer is effective in reducing illness and death, the same conclusion the Task Force reached in 1996. And, despite research showing that pregnant women with bacterial vaginosis (a common condition among women of childbearing age resulting in a vaginal discharge caused by an imbalance in vaginal bacteria) have a higher risk of preterm delivery, evidence does not merit regular screening to reduce the incidence of preterm delivery. For women at high risk due to a previous preterm delivery, however, the USPSTF found conflicting results regarding the benefit of screening and treatment, and concluded that these options be left to the discretion of clinicians.

The skin cancer study was authored by Helfand, Susan McMahon, MP.H., research associate in the OHSU Division of Medical Informatics and Outcomes Research, and Karen Eden Ph.D., assistant professor of medical informatics and outcomes research at OHSU. The bacterial vaginosis study was authored by Jeanne-Marie Guise, M.D., M.P.H., assistant professor of obstetrics and gynecology at OHSU, McMahon and Helfand.

"So many of our health problems can be avoided through healthy lifestyles and preventive health care," said federal Department of Health and Human Services Secretary Tommy G. Thompson. "These screening recommendations are an important step in our efforts to improve the quality of health care and quality of life for all Americans."

The panel is issuing individual updates of the 70 chapters from its 1996 report as they are completed. The recommendations released today and summaries of the evidence on which they are based are published in the April 2001 edition of the American Journal of Preventive Medicine.

USPSTF recommendations, summaries of the evidence, easy-to-read fact sheets and related materials are available from the AHRQ Publications Clearinghouse at 800 358-9295, on the AHRQ Web site at www.ahrq.gov/clinic/prevenix.htm.

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