The state’s largest health insurer is recruiting women it insures to participate in a nationwide study about how frequently women should be screened for breast cancer — whether annual mammograms or a personalized schedule based on risk factors is best.

Horizon Blue Cross Blue Shield of New Jersey announced Tuesday that it would cover the costs for 5,000 women to join the study, which is being conducted by researchers with the University of California medical centers and a Midwestern health system.

Clinical guidelines and experts differ on when women should start to have regular mammograms and how frequently they should do so. The WISDOM study — a creative acronym for Women Informed to Screen Depending on Measures of Risk — aims to improve care by studying the experiences of 100,000 women for five years.

Breast cancer is the most commonly diagnosed cancer among women in New Jersey and the second leading cancer-related cause of death among women. The American Cancer Society projects that 1,250 women will die of breast cancer in New Jersey this year.

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Early detection is an important factor in successful treatment. Yet in 2014, one out of four women over age 40 in New Jersey had not had a mammogram within the previous two years, according to the American Cancer Society.

Improving the screening protocols “can help us close that gap in care and focus on reaching women with a higher risk profile,” said Thomas Graf, Horizon’s chief medical officer.

The insurer's collaboration in the study “helps further Horizon’s goal of connecting members with the right care, in the right setting, at the right time,” said Kevin Conlin, Horizon’s chief executive officer.

The development of better screening guidelines will help “give our physician partners a better tool to help their patients, help women avoid unnecessary tests and procedures, and lower the total cost of care for our members,” he said.

Most doctors and patients currently follow guidelines endorsed by the American College of Obstetricians and Gynecologists and the American College of Radiology that women should begin annual mammograms at age 40. But experts say this may lead to false positives, or results that indicate breast cancer has been detected when it is not present. That, in turn, may lead to unnecessary biopsies, in which samples of breast tissue are removed for microscopic analysis.

The WISDOM study will evaluate a new approach, based on a personalized screening of women for risk factors. It aims to clarify the recommendation of the United States Preventive Services Task Force, an independent volunteer panel of national experts in disease prevention and evidence-based medicine, that women consult with their health care providers about when to start screening before age 50 and have mammograms every other year starting at 50.

"It is time to test a new approach to breast cancer screening that harnesses what we have learned over the last two decades," Dr. Laura Esserman, the study’s principal investigator and director of the Carol Franc Buck Breast Cancer Center at the University of California San Francisco, said in a statement. "Breast cancer is not one disease, and all women are not at risk for the same kind of cancer. We can tailor the amount of screening to what people need."

Study participants will be randomized into two study arms, one receiving annual mammograms and the other receiving mammograms on a personalized schedule. Women with a strong preference for one or the other can choose which to join. All will be asked to complete an annual questionnaire about breast health and to stay in the study for the full five years.

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The personalized schedule will be based on each woman’s answers to a questionnaire about family history, breast density and other risk factors, as well as a genetic test that analyzes her saliva for nine genes related to breast cancer and more than 100 small genetic changes that can add up to increased risk of breast cancer. (Those in the annual-mammography arm of the study will not be given genetic tests, although they can purchase them individually if they wish.)

Based on the personalized assessments, women will be grouped into three risk categories: above average, average and below average. Women at higher risk will be screened more frequently, and those at low risk will be screened less frequently.

Depending on the category, they will be asked to return for a mammogram in six months, a year, or two years — or told to wait until turning 50 to start screening if they are younger than 50.

To participate, women in New Jersey must be Horizon members between the ages of 40 and 74 who have not had a mastectomy, breast cancer or ductal carcinoma in situ, known as DCIS — considered a potentially precancerous diagnosis of abnormal cells in the lining of the milk ducts of the breast. Horizon will cover the costs of all tests associated with the study.

The study is being conducted by the Athena Breast Health Network, a group of breast cancer experts, health care providers, researchers and patient advocates at five University of California Medical Centers (UC Davis, Irvine, Los Angeles, San Diego and San Francisco), and the Sanford Health System in North and South Dakota, Iowa, and Minnesota.

It is funded by the Patient-Centered Outcomes Research Institute and the Robert Wood Johnson Foundation.

Email: washburn@northjersey.com