1 table, 2 figures omitted
Colorectal cancer is the second leading cause of cancer-related death
in the United States.1 The lifetime risk
for having colorectal cancer diagnosed is 6%.2 Screening
measures decrease the incidence and mortality of colorectal cancer by detecting
early disease and removing precancerous lesions.3 The
U.S. Preventive Services Task Force recommends routine cancer screening for
U.S. adults aged ≥50 years with one or a combination of the following screening
options: annual home fecal occult blood testing (FOBT), sigmoidoscopy every
5 years, colonoscopy every 10 years, or double contrast barium enema every
5 years.3 To estimate rates and evaluate
trends for colorectal cancer test use among U.S. adults aged ≥50 years,
CDC analyzed data from the 2001 Behavioral Risk Factor Surveillance System
(BRFSS) on the use of FOBT and sigmoidoscopy/colonoscopy and compared the
data for 2001 with those for 1997 and 1999. This report summarizes the results
of that analysis, which indicate that despite small increases in the self-reported
use of colorectal cancer tests, screening rates remain low. Efforts to increase
awareness and encourage regular colorectal cancer screening should continue.
BRFSS is a state-based, random-digit–dialed telephone survey of
the civilian, U.S. noninstitutionalized population aged ≥18 years. In 2001,
all 50 states, the District of Columbia, Puerto Rico, the Virgin Islands,
and Guam participated in BRFSS. Respondents aged ≥50 years, the age group
for which colorectal cancer screening is recommended, were asked whether they
ever had used "a special kit at home to determine whether the stool contains
blood" (FOBT), whether they ever had "a tube inserted through the rectum to
view the bowel for signs of cancer or other health problems" (sigmoidoscopy/colonoscopy),
and when these tests were last performed. For this report, both sigmoidoscopy
and colonoscopy are described as "lower endoscopy."
Previous reports have examined lower endoscopic surveillance within
5 years as a measure of compliance with screening guidelines.4 Because
BRFSS could not differentiate between sigmoidoscopy and colonoscopy, for this
survey, the surveillance period was 10 years to include those undergoing colonoscopy.
Any respondents reporting lower endoscopy within 10 years were considered
to have been screened within the recommended period. Percentages were estimated
for persons aged ≥50 years who had reported FOBT ever and within the 12
months preceding the survey, lower endoscopy ever and within 5 and 10 years
preceding the survey, and FOBT within 12 months and/or lower endoscopy within
10 years preceding the survey.
For the 2001 BRFSS, the median state response rate was 51.1% (range:
33.3%-81.5%) using the CASRO method.5 A
total of 87,729 persons aged ≥50 years responded. Responses coded as "don't
know/unsure" or "refused" were excluded from analysis (3%-4%). Proportions,
standard errors, and 95% confidence intervals were calculated by using SAS
v8 and SUDAAN. Data were weighted to the age, sex, and race/ethnicity distribution
of the adult population in each state by using intercensal estimates and age
standardized to the 2001 BRFSS population. Estimates for the percentage of
adults aged ≥50 years who self-reported receiving either FOBT within 12
months or lower endoscopy within 5 years (1997 and 1999 surveys did not include
responses within 10 years) were compared for 1997, 1999, and 2001.
In 2001, an estimated 44.6% of adults aged ≥50 years had ever had
FOBT, and 47.3% had ever had a lower endoscopy. An estimated 23.5% had FOBT
within 12 months; 43.4% had lower endoscopy within 10 years; 53.1% had one
or both tests within the periods described. By state, the estimates for FOBT
within 12 months ranged from 6.8% in Alabama to 34.5% in Maine; for lower
endoscopy within 10 years, estimates ranged from 28.4% in the Virgin Islands
to 58.5% in Minnesota. The estimates for reporting either FOBT within 12 months
and/or lower endoscopy within 10 years varied by state from 42.2% in Oklahoma
to 65.3% in the District of Columbia.
The percentage of persons aged ≥50 years who had received FOBT within
12 months was 19.4% in 1997, 20.4% in 1999, and 23.5% in 2001. For lower endoscopy
within 5 years, the proportions were 29.9%, 33.3%, and 38.7%, respectively.
L Seeff, MD, M Nadel, PhD, D Blackman, PhD, Div of Cancer Prevention
and Control, National Center for Chronic Disease Prevention and Health Promotion;
LA Pollack, MD, EIS Officer, CDC.
The findings in this report indicate that colorectal cancer test use
among U.S. adults remains low. Approximately half of U.S. adults aged ≥50
years have not received the recommended screening.
The findings in this report are subject to at least five limitations.
First, the percentages reported overestimate colorectal cancer screening rates
because (1) BRFSS could not differentiate test use specifically for screening
from tests performed for diagnostic purposes and (2) persons who received
sigmoidoscopy outside the recommended 5-year screening interval, but within
10 years, were considered compliant with screening guidelines. As a result,
colorectal cancer screening rates are probably lower than the estimates in
this report. Second, BRFSS excludes residents of institutions and persons
who do not own telephones. Third, estimates from BRFSS were based on self-reports
and were not validated; however, previous studies document moderate-to-good
concordance between the self-reporting of colorectal cancer tests and medical
records.6,7 Fourth, the
response rate of 51.1% is low and has been low in previous years (62.1% in
1997 and 55.2% in 1999).5 Health-care–seeking
behaviors might differ among respondents and nonrespondents. Finally, data
on the use of barium enema, another option for colorectal cancer screening,
were not provided in BRFSS. However, barium enema is recommended less often
than FOBT or sigmoidoscopy.8
Colorectal cancer test screening rates are much lower than breast and
cervical cancer test screening rates (mammography and Papanicolaou smear,
respectively).9 This shortfall warrants
increased public and health-care provider awareness and supportive health-care
systems that emphasize and ensure accessibility to colorectal cancer screening.
In July 2001, Medicare reimbursement was approved for colonoscopy screening
for persons with average risk for colorectal cancer; this measure might increase
future screening rates.
To promote colorectal cancer screening, CDC will launch its annual "Screen
for Life: A National Colorectal Cancer Awareness Campaign" (http://www.cdc.gov/cancer/screenforlife), which encourages persons aged ≥50 years to discuss screening for
colorectal cancer with their doctor and to select appropriate test(s). For
health-care providers, CDC also has produced an education program, "A Call
to Action: Prevention and Early Detection of Colorectal Cancer" (http://www.cdc.gov/cancer/colorctl/calltoaction). In addition, CDC has supported a measure of colorectal cancer screening
for the Health Plan Employer Data and Information Set (HEDIS), a set of standardized
performance measures that permits comparison of managed care organizations.
The measure has been approved provisionally for inclusion in HEDIS in 2004.
To address issues related to mass screening, CDC's Survey of Endoscopy Capacity
will examine the national distribution of lower endoscopes and trained health-care
This report is based on data contributed by state BRFSS coordinators.
Colorectal Cancer Test Use Among Persons Aged ≥50 Years—United States, 2001. JAMA. 2003;289(19):2492–2493. doi:10.1001/jama.289.19.2492