Strongly Divergent Impact of Adherence Patterns on Efficacy of Colorectal Cancer Screening: The Need to Refine Adherence Statistics.
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ABSTRACT: Introduction
The performance of colorectal cancer (CRC) screening programs depends on the adherence to screening offers. However, identical adherence levels may result from varying patterns of the population's screening behavior. We quantified the effects of different adherence patterns on the long-term performance of CRC screening for annual fecal immunochemical testing and screening colonoscopy at 10-year intervals.Methods
Using a multistate Markov model, we simulated scenarios where, while at the same overall adherence level, a certain proportion of the population adheres to all screening offers (selective adherence) or the entire population uses the screening offers at some point(s) of time, albeit not in the recommended frequency (sporadic adherence). Key outcomes for comparison were the numbers of prevented CRC cases and prevented CRC deaths after 50 simulated years.Results
For screening with annual fecal immunochemical testing at adherence levels of 10%-50%, ratios of prevented CRC cases (CRC deaths) resulting from a sporadic vs a selective pattern ranged from 1.8 to 4.4 (1.9-5.3) for men and from 1.7 to 3.6 (1.8-4.4) for women, i.e., up to 4-5 times more CRC cases and deaths were prevented when the population followed a sporadic instead of a selective adherence pattern. Comparisons of simulated scenarios for screening colonoscopy revealed similar patterns.Discussion
Over a lifelong time frame, large numbers of irregular screening attendees go along with much larger preventive effects than small numbers of perfectly adhering individuals. In clinical practice, efforts to reach as many people as possible at least sporadically should be prioritized over efforts to maximize adherence to repeat screening offers.
SUBMITTER: Heisser T
PROVIDER: S-EPMC8437219 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:This study investigated predictors of overall and test-specific colorectal cancer screening (CRCS). Stool blood test (SBT) and/or colonoscopy screening were offered to primary care patients in two randomized controlled trials which assessed the impact of behavioral interventions on screening. Data were obtained through surveys and electronic medical records. Among 1942 participants, 646 (33%) screened. Exposure to interventions was associated with higher overall CRCS by twofold to threefold; older age, African American race, being married, and having a higher screening decision stage were also associated with higher overall CRCS (odds ratios = 1.30, 1.31, 1.34, and 5.59, respectively). Intervention, older age, female gender, and being married were associated with higher SBT adherence, while preference for colonoscopy was associated with lower SBT adherence. Intervention and higher decision stage were associated with higher colonoscopy adherence, while preference for SBT was associated with lower colonoscopy adherence. Among older individuals, African Americans had higher overall CRCS than whites, but this was not true among younger individuals (interaction p = .041). The higher screening adherence of African Americans over whites was due to stronger screening with a non-preferred test, i.e., higher SBT adherence only among individuals who preferred colonoscopy and higher colonoscopy adherence only among individuals who preferred SBT. Intervention exposure, sociodemographic background, and screening decision stage predicted overall CRCS adherence. Gender and test preference also affected test-specific screening adherence. Interactions involving race and test preference suggest that it is important to provide both colonoscopy and SBT screening options to patients, particularly African Americans.
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Project description:BackgroundIn 2014, a national campaign was launched to increase colorectal cancer (CRC) screening rates in the United States to 80% by 2018; it is unknown whether there is sufficient colonoscopy capacity to reach this goal. This study estimated the number of colonoscopies needed to screen 80% of the eligible population with fecal immunochemical testing (FIT) or colonoscopy and determined whether there was sufficient colonoscopy capacity to meet the need.MethodsThe Microsimulation Screening Analysis-Colon model was used to simulate CRC screening test use in the United States (2014-2040); the implementation of a national screening program in 2014 with FIT or colonoscopy with 80% participation was assumed. The 2012 Survey of Endoscopic Capacity (SECAP) estimated the number of colonoscopies that were performed and the number that could be performed.ResultsIf a national screening program started in 2014, by 2024, approximately 47 million FIT procedures and 5.1 million colonoscopies would be needed annually to screen the eligible population with a program using FIT as the primary screening test; approximately 11 to 13 million colonoscopies would be needed annually to screen the eligible population with a colonoscopy-only screening program. According to the SECAP survey, an estimated 15 million colonoscopies were performed in 2012, and an additional 10.5 million colonoscopies could be performed.ConclusionsThe estimated colonoscopy capacity is sufficient to screen 80% of the eligible US population with FIT, colonoscopy, or a mix of tests. Future analyses should take into account the geographic distribution of colonoscopy capacity. Cancer 2016;122:2479-86. © 2016 American Cancer Society.
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Project description:BACKGROUND AND AIMS:Colorectal cancer (CRC) screening can reduce CRC incidence and mortality, but measuring screening adherence over time is challenging. We examined adherence using a novel measure characterizing the proportion of time covered (PTC) by screening tests. METHODS:Eligible patients were age 50 to 60 years and followed at a large, safety-net health care system between January 2010 and September 2014. We estimated PTC as the number of days up to date with screening divided by the number of days from cohort entry until study end, CRC diagnosis, or death. We estimated mean and median PTC and used least-significant difference tests to assess differences in adherence by patient characteristics. RESULTS:Of 18,257 patients, most were non-Hispanic black (40.5%) or Hispanic (34.9%) and/or female (62.4%). Approximately 40% (n = 7559) were never screened during the study period; the remaining 10,698 patients completed 19,105 screening examinations (14,481 fecal immunochemical tests [FITs], 4393 colonoscopies, 94 sigmoidoscopies, and 137 barium enemas). Overall, the mean PTC was 29.1% (95% confidence interval [CI], 28.6%-29.5%). Among those who completed at least one screening test (n = 10,698), the mean PTC was 49.0% (95% CI, 48.5%-49.5%). The most common reasons for non-adherence were lack of repeat FIT and no diagnostic colonoscopy after abnormal results for the FIT. The mean PTC increased with the number of primary care visits (0 visits, 21%; 1 visit, 29%; 2-3 visits, 35%; ?4 visits, 37%; all P < .05). CONCLUSIONS:PTC provides a reliable estimate of screening adherence, capturing breakdowns in the CRC screening process amenable to intervention. Repeat FIT and diagnostic colonoscopy are important intervention targets that may increase adherence in underserved populations.
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Project description:BackgroundDespite evidence that several colorectal cancer (CRC) screening strategies can reduce CRC mortality, screening rates remain low. This study aimed to determine whether the approach by which screening is recommended influences adherence.MethodsWe used a cluster randomization design with clinic time block as the unit of randomization. Persons at average risk for development of CRC in a racially/ethnically diverse urban setting were randomized to receive recommendation for screening by fecal occult blood testing (FOBT), colonoscopy, or their choice of FOBT or colonoscopy. The primary outcome was completion of CRC screening within 12 months after enrollment, defined as performance of colonoscopy, or 3 FOBT cards plus colonoscopy for any positive FOBT result. Secondary analyses evaluated sociodemographic factors associated with completion of screening.ResultsA total of 997 participants were enrolled; 58% completed the CRC screening strategy they were assigned or chose. However, participants who were recommended colonoscopy completed screening at a significantly lower rate (38%) than participants who were recommended FOBT (67%) (P < .001) or given a choice between FOBT or colonoscopy (69%) (P < .001). Latinos and Asians (primarily Chinese) completed screening more often than African Americans. Moreover, nonwhite participants adhered more often to FOBT, while white participants adhered more often to colonoscopy.ConclusionsThe common practice of universally recommending colonoscopy may reduce adherence to CRC screening, especially among racial/ethnic minorities. Significant variation in overall and strategy-specific adherence exists between racial/ethnic groups; however, this may be a proxy for health beliefs and/or language. These results suggest that patient preferences should be considered when making CRC screening recommendations. Trial Registration clinicaltrials.gov Identifier: NCT00705731.
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Project description:Current recommendations of The US Preventive Services Task Force (USPSTF) on colorectal cancer (CRC) screening strategies are based on models that assume 100% adherence. Since adherence can have a large effect on screening outcomes, we aimed to compare the effectiveness of CRC screening strategies under reported adherence rates at the population level. We developed and validated a microsimulation model to assess the effectiveness of colonoscopy (COL), flexible sigmoidoscopy (FS), high-sensitivity guaiac fecal occult blood-test (HS-gFOBT), fecal immunochemical test (FIT), multitarget stool DNA test (FIT-DNA), computed tomography colonography (CTC), and methylated SEPT9 DNA test (SEPT9) in terms of CRC incidence and mortality, incremental life years gained (LYG), number of colonoscopies, and adverse events for men and women 50 years or older over their lifetime. We assessed outcomes under 100% adherence rates and reported adherence rates. We also performed sensitivity analyses to evaluate the impact of varying adherence levels on CRC outcomes. Assuming 100% adherence, FIT-DNA, FIT, HS-gFOBT, and SEPT9 averted 42-45 CRC cases and 25-26 CRC deaths, COL 46 cases and 26 deaths, CTC 39 cases and 23 deaths, FS 32 cases and 19 deaths per 1000 individuals. Assuming reported adherence, SEPT9 averted 37 CRC cases and 23 CRC deaths, COL 34 cases and 20 deaths, FIT-DNA, FIT, CTC and HS-gFOBT 16-25 cases and 10-16 deaths per 1000 individuals. LYG reflected the effectiveness of each strategy in reducing CRC cases and deaths. Adverse events were more common for COL (3.7 per 1000 screened) and annual SEPT9 (3.4 per 1000 screened), and proportional to the number of colonoscopies. Among the screening strategies recommended by USPSTF, colonoscopy results in the largest benefit when we account for adherence. Adherence rates higher than 65%-70% would be required for any stool or blood-based screening modality to match the benefits of colonoscopy.
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