Physician recommendations vary on when to start and stop mammograms for breast cancer screening — and how often to screen patients in between, according to a new study in the Journal of the American Medical Association Internal Medicine.

Why it matters: Doctor recommendations are one of the most important factors determining whether and when patients get screened for breast cancer. Breast cancer can be detected — and then treated — earlier with mammograms, but there is a risk of false positives and unnecessarily treating the disease. The study "suggests a large proportion of primary care physicians recommend screening mammography for women who are more likely to experience harms than benefits from the examination," per researchers not involved in the study.