Maybe it is out of fear, but only about 15 percent of American women over 50 have an annual mammogram, even though it is considered a must.

Yet, if a cancer is detected before a breast lump can be felt, the chance of survival increases by 30 percent.Mammography is not without risk, whether of radiation or human error. The November issue of Lear's magazine offers some tips on what to look for when scheduling a mammogram.

- X-ray equipment should be used only for mammography. There are two types: film-screen (the image appears on X-ray film with a screen that amplifies the radiation) and Xeroradiography (the image appears on paper rather than film). Film-screen emits less radiation, even with a grid to improve picture quality, although Xerox has introduced a system on a limited scale that cuts dosage levels to below the film-screen-grid.

- X-ray equipment should be well maintained. Most states conduct their own inspections or consign them, generally on an annual basis.