Pap smear tests are the primary screening tool for cervical cancer. Since doctors began using Pap smears regularly in the mid-1950s, deaths from cervical cancer have decreased 74 percent. Pap smears detect abnormal cells in the cervix, which can be treated before they develop into cancer. Pap smears sometimes are inaccurate and require retesting, but new liquid-based technologies have made them more effective.

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