The HEDIS Colorectal Cancer Screening (COL) Measure: A Complete Guide for Health Plans

Colorectal cancer is highly preventable, and yet the Colorectal Cancer Screening (COL) measure still lands on most quality teams' list of underperforming measures year after year. The science here isn't in question - the hard part is getting an eligible member to engage in a traditionally very invasive procedure. This guide walks through what the COL measure covers, why colorectal cancer screening carries the weight it does, which tests count, and how at-home testing has become one of the better tools health plans have for closing this gap.

What Is HEDIS, and What Does the COL Measure Require?

HEDIS, the Healthcare Effectiveness Data and Information Set, is the quality measurement framework the National Committee for Quality Assurance (NCQA) uses to evaluate health plans. More than 90% of U.S. health plans report HEDIS data, and for Medicare Advantage plans specifically, HEDIS performance feeds directly into Star Ratings and the billions of dollars in quality bonus payments tied to them.

The COL measure evaluates whether members ages 45 to 75 received appropriate colorectal cancer screening within the required interval for the test they used. NCQA updated the eligible age range down from 50 to 45 to align with current screening guidelines, which widened the at-risk population every plan is now responsible for reaching. A member counts toward the measure the moment a qualifying test is completed and documented, regardless of which test they chose.

Colorectal Cancer, by the Numbers

The American Cancer Society estimates roughly 158,850 new colon and rectal cancer cases and 55,230 deaths in 2026, which makes colorectal cancer the second-leading cause of cancer death in the U.S. when men and women are combined. Incidence in adults over 50 has been falling for decades, largely thanks to screening. That's not true under 50: rates in that group have climbed roughly 2.9% a year since 2013, and colorectal cancer is now the leading cause of cancer death for adults under 50.

Screening still isn't reaching enough of the eligible population. More than 20 million eligible Americans have never been screened, and roughly 1 in 3 adults haven't completed a recommended screening at all. Only 63.5% of adults ages 45 to 75 were up to date on screening in 2023, well short of the Healthy People 2030 target of 72.8%. It's worth closing that gap. Cancer caught early, while it's still localized, has a five-year survival rate above 90%, and not many HEDIS measures line up this cleanly with what's actually good for the member.

The Screening Tests That Count Toward COL

NCQA and the American Cancer Society's 2026 guideline update both recognize several test types, and a member only needs to complete one within its required interval. The U.S. Multi-Society Task Force on Colorectal Cancer ranks these options into tiers based on the strength of the evidence behind them, how available they are, and how likely members are to actually repeat them on schedule. Colonoscopy and FIT share the top spot, Tier 1.

• FIT (fecal immunochemical test), annually. A stool sample collected at home and mailed to a lab, FIT checks for hidden blood, an early signal of polyps or cancer. It requires no dietary restrictions or prep, and it's the only Tier 1 option that doesn't require a clinical visit.
• Colonoscopy, every 10 years. The only screening option that lets a physician find and remove polyps in the same procedure. It also requires bowel prep, sedation, a driver, and typically a day away from work — enough friction on its own to keep completion rates low among members who'd otherwise qualify for something less invasive.
• Stool DNA/RNA tests, every 3 years. Cologuard and newer stool RNA tests like ColoSense analyze a stool sample for DNA or RNA markers alongside hemoglobin. Sensitivity is high for cancer and moderate for precancerous polyps, and like FIT, the sample is collected entirely at home.
• CT colonography and flexible sigmoidoscopy, every 5 years. Structural exams that still require a clinical visit, though less invasive than a full colonoscopy.
• Blood-based tests, every 3 years. Guardant Health's Shield test received FDA approval in 2024 and is now Medicare-covered for members 45 and older. The American Cancer Society lists blood-based testing as a non-preferred option, since it detects existing cancer better than it detects precancerous lesions, and a positive result still requires a follow-up colonoscopy. Think of it as a fallback for members who won't do anything else, rather than a first choice.

Why Screening Rates Still Fall Short

Most eligible members already have coverage for one of these tests at no cost, so access on its own doesn't explain why so many stay unscreened. What they're missing is an easy path to using the benefit they have. A colonoscopy referral asks someone to schedule a specialist visit weeks out, line up a ride, take a day off work, and get through a bowel prep regimen plenty of people find unpleasant enough to keep putting off. Even FIT and stool DNA tests, which skip all of that, still depend on a member getting a kit, reading the instructions, and mailing it back.

Quality teams often treat this as an awareness problem and respond with more education and more reminders. In practice it's usually a completion problem. Members already know the screening exists; they just haven't gotten around to finishing it, and a reminder letter rarely moves someone who's had months to schedule a colonoscopy and still hasn't. Closing this gap takes outreach built around removing friction, not repeating the ask.

At-Home Testing: A Lower-Cost Path to Closing the Gap

FIT and stool DNA testing are already at-home by design, which makes colorectal cancer screening one of the more straightforward HEDIS measures to activate at scale. A kit ships directly to the member's door under the plan's own brand, the member completes the sample on their own schedule, and it goes back through a prepaid mailer instead of a lab visit. There's no facility fee, no anesthesia, and no missed shift to coordinate around, which is a large part of why FIT-based outreach consistently outperforms colonoscopy referrals for members who haven't engaged with clinical care in years.

Outreach still matters even once the kit is in hand. Health plans running coordinated email, SMS, and IVR outreach alongside kit delivery see meaningfully higher completion than plans relying on a single mailed reminder, since each touchpoint has a shot at catching a different member when they're ready to act.

Ash has put this model to work with a national health plan struggling to reach its "non-engagers," members who'd already been sent a FIT kit and never returned it. The plan re-engaged 6,000 of its hardest-to-reach members, boosting FIT return rates in that group went from 0% to roughly 11%Along the way, the program also surfaced members who'd already completed a colonoscopy on a previous plan, closing those gaps administratively instead of shipping kits that weren't needed. Read the full breakdown in Ash's national health plan case study. For a closer look at how FIT compares with colonoscopy in practice, see Colorectal Cancer Screening Options: At-Home FIT vs. Colonoscopy.

Building a COL Gap Closure Program That Works

A member who gets a kit in the mail, knows what to do with it, and gets a nudge if it doesn't come back within a few weeks is far more likely to close their gap than one waiting on a specialist referral to work its way through the calendar. Plans that make screening easy to finish tend to outperform plans that only make it easy to start, and that difference is really what the COL measure comes down to.

If your plan is building or refining a colorectal cancer screening program, Ash can help. We support the COL measure with white-labeled FIT kits, multi-channel member engagement, and dedicated clinical oversight, all built to close gaps before the measurement year runs out.

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