U.S. adults should choose the type of colon cancer screening they feel most comfortable with, the government-backed U.S. Preventive Services Task Force now advises.

The updated recommendation, directed at people ages 50 to 75 years, is a departure from the influential panel's 2008 guidance, which said people in that age group should be screened on a specific time table using one of four tests.

Multiple options for colorectal cancer screening are effective, said Dr. Douglas Owens, a former member of the USPSTF who worked on the new recommendation. "Our recommendation is people discuss the strengths and limitations of the different options with their clinicians," he said. "Make a choice they can follow through with."

"What really matters is they get screened for colorectal cancer," he told Reuters Health.

One in 21 U.S. men and one in 23 women can expect to develop colon or rectal cancers, according the American Cancer Society.

Despite research showing that screening can reduce the risk of death from these malignancies, testing rates remain low. A May 2015 study from the U.S. Centers for Disease Control and Prevention found only 25 percent of uninsured people and 60 percent of insured people were being screened for colon cancer as recommended.

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"In the current recommendation, instead of emphasizing specific screening approaches, the USPSTF has instead chosen to highlight that there is convincing evidence that colorectal cancer screening substantially reduces deaths from the disease among adults aged 50 to 75 years and that not enough adults in the United States are using this effective preventive intervention," the USPSTF wrote in JAMA on Wednesday.

Previously, the USPSTF recommended that people ages 50 to 75 be screened with either a colonoscopy, either of two stool analyses known as fecal immunochemical testing or high-sensitivity fecal occult blood testing, or flexible sigmoidoscopy combined with fecal occult blood test.

In addition to those tests, the USPSTF also says people can be screened using CT colonography, which uses a low-dose radiation CT scan to see the inside of the colon.

The different methods of testing need to be repeated at varying intervals (see timetable here: http://bit.ly/1UjVV5A).

For example, flexible sigmoidoscopy should be repeated every five years, or every 10 years if it's combined with fecal occult blood testing.

While the benefits of screening outweigh the potential harms, the USPSTF cautions that a positive test may lead to additional screening and procedures.

If, for example, a feces test is positive, the patient would likely go on to have a colonoscopy, said Owens, who is also affiliated with Stanford University in California.

"The harms from colonoscopy are small relative to the benefits, but that's where the harms primarily come from," he added.

For people ages 76 to 85 years, the USPSTF says screening for colon cancer should be a personal decision that takes overall health and prior screening history into account.

"The people who would be most likely to benefit are people who have not been screened before, people who are healthy enough to undergo treatment for colorectal cancer and people who don't have other conditions that would limit their life expectancy substantially," Owens told Reuters Health.