Communication
How Many Individuals Will Need to Be Screened to Increase Colorectal Cancer Screening Prevalence to 80% by 2018? Stacey A. Fedewa, MPH1,2; Jiemin Ma, PhD1; Ann Goding Sauer, MSPH1; Rebecca L. Siegel, MPH1; Robert A. Smith, PhD3; Richard C. Wender, MD3; Mary K. Doroshenk, MA3; Otis W. Brawley, MD4; Elizabeth M. Ward, PhD1; and Ahmedin Jemal, PhD1
BACKGROUND: A recent study estimates that 277,000 colorectal cancer (CRC) cases and 203,000 CRC deaths will be averted between 2013 and 2030 if the National Colorectal Cancer Roundtable goal of increasing CRC screening prevalence to 80% by 2018 is reached. However, the number of individuals who need to be screened (NNS) to achieve this goal is unknown. In this communication, the authors estimate the NNS to achieve 80% by 2018 nationwide and by state. METHODS: The authors estimated the NNS by subtracting adults aged 50 to 75 years who would need to be screened to achieve an 80% CRC screening prevalence from the number who are currently guideline-compliant from population estimates for this age group. The 2013 National Health Interview Survey and the 2012 Behavioral Risk Factor Surveillance System were used to estimate CRC screening prevalence and data from the US Census Bureau were used to estimate population projections. The NNS were age-standardized and sex-standardized. RESULTS: Nationwide, 24.39 million individuals (95% confidence interval, 24.37-24.41 million) aged 50 to 75 years will need to be screened to achieve 80% by 2018. By state, the NNS ranged from 45,400 in Vermont to 2.72 million in California. The majority of individuals who need to be screened are aged 50 to 64 years and the largest subgroup is privately insured. CONCLUSIONS: The authors estimated that at least 24.4 million additional individuals in the United States will need to be screened to achieve the National Colorectal Cancer Roundtable goal of increasing CRC screening prevalence to 80% by 2018. To reach this goal, improving facilitators of CRC screening, including C 2015 American Cancer Society. physician recommendation and patient awareness, is needed. Cancer 2015;121:4258-65. V KEYWORDS: cancer screening, colorectal neoplasms, National Colorectal Cancer Roundtable, public health, socioeconomic status.
INTRODUCTION The American Cancer Society estimates that in 2015, 132,700 men and women in the United States will be diagnosed with colorectal cancer (CRC) and 49,700 individuals will die of the disease.1 Although the large declines in CRC incidence and mortality in recent years have mainly been attributed to improved early detection and screening,2,3 in 2013, only approximately 57% of eligible adults were up-to-date with US Preventive Services Task Force (USPSTF) CRC screening recommendations.4 The benefits of CRC screening are well recognized by the cancer research, control, and public health communities.5,6 To help address the need for increased CRC screening, in 2014, the National Colorectal Cancer Roundtable (NCCRT), a coalition aimed at reducing CRC incidence and mortality, initiated a nationwide goal of increasing CRC screening prevalence to 80% by 2018.7 A recent study estimates that 277,000 CRC cases and 203,000 CRC deaths will be averted between 2013 and 2030 if the 80% by 2018 goal is reached.8 However, it is not known how many additional individuals will need to receive screening to meet this goal, which will be useful for >300 organizations who have joined this NCCRT initiative. In this communication, we estimate the number of individuals who need to be screened (NNS) nationwide and by state to achieve the NCCRT goal of 80% screening prevalence by 2018. MATERIALS AND METHODS Data Sources
The 2 most recent available data sources, the 2013 National Health Interview Survey (NHIS) and the 2012 Behavioral Risk Factor Surveillance System (BRFSS), were used to estimate current CRC screening prevalence for adults aged 50 to 75 years based on USPSTF recommendations.6 The 2013 NHIS data were used to estimate nationwide sex-specific and
Corresponding author: Stacey A. Fedewa, MPH, Surveillance and Health Services Research, American Cancer Society, 250 Williams St, Atlanta, GA 30303; Fax: (404) 321-4669;
[email protected] 1 Surveillance and Health Services Research, American Cancer Society, Atlanta, Georgia; 2Department of Epidemiology, Emory University, Atlanta, Georgia; 3Cancer Control Science, American Cancer Society, Atlanta, Georgia; 4Office of the Chief Medical Officer, American Cancer Society, Atlanta, Georgia
Additional supporting information may be found in the online version of this article. DOI: 10.1002/cncr.29659, Received: May 21, 2015; Revised: July 20, 2015; Accepted: July 21, 2015, Published online August 26, 2015 in Wiley Online Library (wileyonlinelibrary.com)
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age-specific CRC screening prevalence (n 5 13,125). The overall response rate for the 2013 NHIS was 62.6%. The NHIS is an in-person household survey of noninstitutionalized adults aged 18 years and is designed to provide national and regional prevalence estimates regarding sociodemographic and health data in the United States.9 The 2012 BRFSS data were used to estimate age-standardized and sex-standardized CRC screening prevalence for each state and Washington, DC (n 5 221,516). In 2012, the BRFSS response rate was 45.2%.10 BRFSS is a monthly, computer-assisted, telephonebased survey of adults aged 18 years and is designed to provide state-level estimates for health behaviors.11 The survey methods were generally comparable from state to state. US Census data were used to estimate the nationwide age- and sex-specific populations as of July 1 in 2015 and 2018 for individuals aged 50 to 75 years.12 The 2015 census data were used to calculate the number of individuals currently up-to-date with CRC screening as described below. Age was grouped as 50 to 64 years and 65 to 75 years. Because the US Census Bureau only produced state-specific population data through 2012, we applied the nationwide age-specific and sex-specific growth rates to each state to estimate the 2015 and 2018 population in the 50 states and Washington, DC. Hereafter, the term “state” will refer to all 50 states plus Washington, DC. Outcome and Statistical Analyses
Up-to-date CRC screening was defined as colonoscopy within the past 10 years, at-home fecal occult blood test (FOBT) or fecal immunochemical test (FIT) within the past year, or flexible sigmoidoscopy within the past 5 years with a FOBT performed every 3 years for individuals aged 50 to 75 years.6 The nationwide mean CRC screening prevalence was 7% higher in the BRFSS compared with the NHIS. Variations in nationwide prevalence estimates for preventive services between the BRFSS and NHIS have been described previously; however, to the best of our knowledge there is no standardized formula to account for these differences.13 We performed a basic adjustment to help account for the potential overestimation of CRC screening prevalence in the BRFSS using formula 1 (shown below), which incorporates differences in NHIS and BRFSS CRC screening prevalence by geographic region, sex, and age. First, we estimated the agespecific (aged 50-64 years and 65-75 years), sex-specific, and region-specific (Northeast, Midwest, South, and West) prevalence of CRC screening in the NHIS and BRFSS to establish 16 stratum-specific CRC screening Cancer
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estimates for each data source. We used region-specific NHIS estimates as a proxy for state-specific estimates as region was the smallest geographic area for which estimates could be calculated using publicly available NHIS data. Second, we divided the NHIS stratum-specific estimate with the corresponding BRFSS estimate to calculate a correction ratio, which was 80%) and visiting a general practitioner within the past 12 months (65.6%), although a substantial minority did not see a practitioner within the previous year. These findings highlight the opportunity for primary care and family physicians to discuss the importance of CRC screening and the benefits and limitations of the various testing options during office visits. The use of electronic medical records and reminder sys4262
TABLE 3. Characteristics of Adults Aged 50 to 75 Years Who Are Not Up-to-Date With USPSTF CRC Screening Recommendations: NHIS, 2013 (n55651) %
95% CI
Insurance Private only 46.7 Medicaid/state plan only 5.6 Medicare only 12.1 Medicare plus Medicaid 3.4 Medicare plus private 8.6 Uninsured 18.8 Other 4.9 Has a usual source of care Yes 83.8 No 16.2 Has visited PCP within past 12 mo Yes 65.6 No 34.5 Ever received CRC screeninga Yes 20.3 No 79.7 Physician recommended colon/rectum test within past problemb Yes 12.1 No 87.8 Race/ethnicity Hispanic 13.4 NH white 69.8 NH black 10.9 NH Asian 5.1 NH American Indian/Alaska Native 0.7 NH other 0.1 Sex Male 49.1 Female 50.9 Age, y 50-64 77.7 65-75 22.4 Education 11 y 17.5 12 y or GED 29.8 13-15 y or AA degree 28.4 16 y 24.4 Immigration status Born in US 80.8 US territory or outside/US < 10y 2.1 US territory or outside/US 10 y 17.1
45.0 4.9 11.0 2.9 7.6 17.5 4.2
48.3 6.4 13.3 4.0 9.6 20.2 5.7
82.6 15.0
85.0 17.4
63.9 32.9
67.1 36.1
19.0 21.6 78.4 81.0 12 mo due to a 11.0 86.7
13.3 89.0
12.3 68.3 9.9 4.4 0.4 0.0
14.6 71.2 12.0 5.9 1.1 0.3
47.4 49.2
50.8 52.7
76.2 21.0
79.0 23.8
16.2 28.1 26.9 22.9
18.8 31.4 29.9 26.1
79.4 1.6 15.9
82.2 2.7 18.4
Abbreviations: 95% CI, 95% confidence interval; AA, Associates degree; CRC, colorectal cancer; GED, General Educational Development; NH, nonHispanic; NHIS, National Health Interview Survey; PCP, primary care physician; USPSTF, US Preventive Services Task Force. a Ever received CRC screening includes individuals who are not-up-to date with CRC screening but have undergone at least one colonoscopy, fecal occult blood test, fecal immunochemical test, or sigmoidoscopy in their lifetime. b Physician recommended a test to examine the colon/rectum due to a problem.
tems facilitate physician recommendations for CRC screening.22,23 With an organized approach to screening, at least 1 integrated health systems in the United States has already achieved 80% CRC prevalence among its enrollees.22,23 In 2007, Kaiser Permanente Northern California launched its organized screening program, which Cancer
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included mailing FIT kits to the homes of screeningeligible enrollees annually and patient reminder systems (telephone and electronic), as well as health provider reminder components. Since Kaiser Permanente Northern California launched its program, CRC screening adherence increased from 37% in 2005 to 79% in 2011.24 Concerted efforts are needed to reach those from low socioeconomic status populations who face unique barriers to CRC screening. According to the findings of the current article, 75.6% of unscreened individuals have less than a 4-year educational degree and although most individuals who were not up-to-date with CRC screening have private or Medicare insurance, uninsured and Medicaid-insured adults have particularly low CRC screening prevalence. According to 2013 NHIS data, only 25% of uninsured and 36% of Medicaid-insured adults (representing 10.4% and 3.6%, respectively, of CRC screening-eligible adults) were up to-date with USPSTF CRC screening recommendations compared with at least 60% of privately or Medicare-insured adults.25 There have been some successful efforts to address this barrier in certain segments of the population. In 2003, Delaware funded its state cancer control program to pay for CRC screening tests and nurse navigators for the uninsured, increasing the percentage of individuals who had ever received colonoscopy from 48% to 58% in 2001 to 73% in 2009.14 The program also eliminated racial disparities in screening and mortality during this time.14,26 Massachusetts, which has provided near universal health care coverage for its citizens since 2006, has the nation’s highest CRC screening prevalence at 76% according to the BRFSS (and 67% after correcting for potential overestimation).4,27 The Patient Protection and Affordable Care Act may address some access issues through the expansion of Medicaid in those states opting in.28 The federal health insurance marketplace, which began in 2014, also may help to reduce the percentage of uninsured, CRC screening-eligible adults. The significant percentage of individuals who are not up-to-date with CRC screening recommendations who have health insurance points to the need to address other barriers to screening beyond access. Other barriers to CRC screening include a patient’s lack of knowledge, trust, fear, cost, and logistical barriers.17,18,29,30 Lack of awareness is one of the most common patient-reported barriers for not receiving CRC screening.18,29 Media coverage and community promotional campaigns aimed at increasing awareness and use of CRC screening have led to short-term gains.31 Among the educational and community interventions aimed at increasing CRC screening Cancer
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awareness, 1-on-1 interventions with health care providers (eg, physicians or nurses) were more effective than small media interventions (eg, video or brochures).32 Patient navigators have been shown to increase CRC screening uptake among economically and socially disadvantaged adults.33,34 Increasing the use of educational tools and patient navigators may increase the knowledge of and use of CRC screening. There are several cultural and cognitive-emotional barriers to CRC screening such as a fear of cancer being found as well as fear of the screening test itself.30,35 Obstacles specific to colonoscopy include a fear of perforation or discomfort during the procedure, anxiety concerning the bowel preparation, and embarrassment.35 There are also financial barriers to CRC screening, which may be independent of the issue of access to care discussed above, because financial barriers have been noted even among the insured.36,37 For example, before 2011, Medicare recipients may have been responsible for up to 20% of the allowable charge for CRC screening tests, although the Patient Protection and Affordable Care Act removed cost sharing for non-grandfathered private health plans.38 The Centers for Medicare and Medicaid Services also approved this provision for Medicare recipients, although some Medicare recipients may still be charged if a polyp is removed and deemed diagnostic due to a loophole in this provision that states that cost sharing is removed for screening tests only.39 Logistical barriers, such as transportation issues, the need for a chaperone, and the inability to take time off of work, are also impediments to CRC screening.30,35 FOBT or FIT are important CRC screening options for individuals with these logistical issues because they are noninvasive and can be completed at home. To our knowledge, the current study is the first to estimate the NNS to achieve the NCCRT screening prevalence goal of 80% by 2018. Previous studies from 2004 and 2005 have estimated the number of colonoscopies that would need to be performed to achieve 70% and 75%, respectively, CRC screening adherence within the context of health care capacity and economic outcomes.40-42 These studies from the early 2000s estimated that meeting screening goals would require considerable use of FIT/FOBT in addition to colonoscopy because the expected demand for colonoscopy would outpace the supply of gastroenterologists during the study period.40,42 This was particularly true for the “catch-up” period, during which unscreened individuals need to be screened, compared with the “steady-state” period, during which only maintenance colonoscopies would need to be performed.41,42 To the best of our knowledge, recent studies 4263
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of endoscopic capacity have not been conducted, although the projected scenarios of nearly exclusive colonoscopy use for CRC screening in the above-mentioned studies are similar to what is currently observed, with colonoscopy accounting for >90% of CRC screening.4042 Another important consideration with respect to the supply of practicing gastroenterologists is that the availability of colonoscopy is lower in rural areas and in counties with higher percentage of Hispanic and blacks individuals compared with urban areas and in counties that are predominately non-Hispanic white.43-45 The current study has several limitations. First, CRC screening estimates were based on self-report and although the concordance between self-reported CRC screening and medical records is good, CRC screening in the current study is likely overestimated due to recall bias as well as selection bias in health-related surveys, leading to an underestimation of the number of individuals in need of CRC screening.14,46 We assumed that those who are currently up-to-date with CRC screening would remain adherent throughout our study period, which also contributes to a conservative estimate of the NNS given that not everyone will stay current with screening, particularly those who rely on the FOBT because it is required annually and long-term adherence in community practice may be suboptimal.47 In addition, we assumed that the 2013 CRC screening patterns from the NHIS were the same in 2015 based on recent estimates that overall CRC screening prevalence has remained relatively stable since 2008; according to 2010 and 2013 NHIS data, CRC screening prevalence was very similar at 58.2% and 57.2%, respectively. However, certain subgroups, including blacks and those insured by Medicare only, have experienced increases in CRC screening prevalence in recent years.48 We did not consider race/ethnicity in the current analyses due to inadequate sample sizes for age-specific, sex-specific, and race/ethnic-specific CRC screening estimates in some states and the race/ethnicity classifications in state census estimates and nationwide projections were not comparable. We estimated that at least 24.4 million individuals in the United States will need to be screened to achieve the NCCRT goal of 80% CRC screening prevalence by 2018. The majority of those in need of CRC screening are aged 50 to 64 years, have less than a 4-year educational degree, and have visited a primary care clinician within the past 12 months; close to one-half of these individuals are privately insured. These observations underscore the opportunity for health care professionals to implement evidence-based systematic approaches to increasing CRC 4264
screening. Additional efforts aimed at taking advantage of insurance coverage for CRC screening, reaching populations of lower socioeconomic status, and increasing patient awareness of CRC screening are also essential to achieve the NCCRT goal of increasing CRC screening prevalence to 80% by 2018. FUNDING SUPPORT Supported by the American Cancer Society.
CONFLICT OF INTEREST DISCLOSURES The authors made no disclosures.
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