Joscelyn Benninghoff, 10, goes over the results of her cholesterol test with her mother Elizabeth Duruz (right) and Dr. Elaine Urbina at Cincinnati Children's Hospital in 2011. Al Behrman/AP hide caption

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Mammograms are a key screening tool for breast cancer. But critics say they're not good enough. Salih Dastan/iStockphoto hide caption

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Insurers still charge copays for some contraceptives. Laura Garca/iStockphoto hide caption

itoggle caption Laura Garca/iStockphoto

Stacy Riggs of Fairfax, Va., is prepped for a screening for atrial fibrillation by Life Line Screening medical assistant Kennea Blake at Messiah United Methodist Church in Springfield, Va. Jenny Gold/Kaiser Health News hide caption

itoggle caption Jenny Gold/Kaiser Health News

Some images of lung cancer are clear cut. But in many others, a nodule on the screen turns out not to be cancer at all. iStockphoto.com hide caption

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