Colorectal cancer (CRC) is a primary cause of cancer-related mortality in the United States. Asian Americans have the highest CRC mortality rates. CRC screening tests can reduce CRC incidence, yet Asian Americans, specifically the subgroup of Vietnamese Americans, underuse CRC screening. The purpose of this phenomenological study was to understand why Vietnamese Americans, ages 50 to 75, underuse CRC screening. The health belief model constructs of susceptibility, severity, benefits, barriers, and self-efficacy were the framework for understanding this population's health-related behaviors. Three research questions focused on how knowledge, language, and cultural beliefs and perceptions affect Vietnamese Americans' CRC screening decisions. Interviews were conducted with 11 participants, and transcribed interview responses were input into NVivo 11 software to maintain a reliable database and to identify emerging themes. Key study findings revealed knowledge and English language gaps as well as adverse cultural perceptions of fear and doubt that influenced CRC screening choices among these 11 Vietnamese Americans. Future researchers might focus on cultural-tailored strategies to minimize these barriers for Vietnamese Americans. An understanding of this study population's perspectives offers the promise of positive social change for health services and public health administrations to develop cultural-tailored interventions that promote healthy lifestyles, prevention, early CRC detection and, consequently, reduce mortality rates and associated health care costs.

Degree awarded (2003): EdDHRD, Counseling, Human and Organizational Studies, George Washington University / ABSTRACT OF DISSERTATION<p>The Effect of Patient Race upon Physicians Colorectal Cancer Screening: A Retrospective Medical Record Review and Physician Pattern Variable Analysis<p>There is a significant disparity in the health status of African-Americans and whites in the United States. Studies have revealed that African-Americans have higher mortality rates from colorectal cancer than whites. Differences in colorectal cancer screening of African-Americans compared to whites may account for a proportion of the excess mortality. This study evaluated internal medicine resident physicians colorectal cancer screening practices in African-American and white patients. Additionally, an analysis of physicians pattern variable orientation was performed to determine if there was a relationship between physicians orientation and adherence to colorectal cancer screening guidelines.<p>A retrospective review of medical records from January 2002 through March 2002 was conducted to assess internal medicine resident physicians performance of colorectal cancer screening. Univariate analysis revealed that there were statistically significant differences in the rate at which physicians performed rectal examinations (p=0.0039), fecal occult blood testing (p=0.0006) and colonic examinations (p<0.0001) in African-American compared to white patients. Multivariate analysis, evaluating patient race, patient gender, patient age and physician gender, demonstrated that patient race was the only factor significant for not performing colorectal cancer screening tests.<p>Physicians perspectives about the medical profession and the delivery of medical services were assessed by evaluating pattern variable orientations. Integrative, value and motivational orientations of the physicians were determined by using semi-structured interviews. All of the physicians had a self-orientation (integrative pattern variable), a universalistic-achievement orientation (value pattern variables) and a specificity orientation (motivational pattern variable). However, the physicians differed in their affectivity-affective neutrality orientation (motivational pattern variable). All of the physicians who had an affective orientation toward their patients adhered to colorectal cancer screening recommendations. The physicians who expressed affective neutrality toward their patients did not adhere to colorectal cancer screening recommendations.<p>This study revealed significant differences in the performance of colorectal cancer screening in African-American compared to white patients. Additionally, physicians pattern variable orientations correlated with adherence to practice guidelines. This study is important because it provides information about physician practice patterns. The results of this study can serve as the basis for the development of educational interventions for physicians that can improve health care delivery. / Advisory Committee: Dr. John Williams, Dr. David Schwandt (Chair), Dr. Andrea Casey, Dr. Jeffrey Lenn, Dr. Victor Scott

Colorectal cancer (CRC) is one of the most common causes of death from malignant disease. Nevertheless, no ideal screening method exists and there is a lack of prognostic and predictive factors to support clinical decisions and to aid the development of a more individualized treatment for patients with CRC. The aim of this thesis was to investigate early detection, prognostic and predictive factors of CRC. In the first paper, a novel method to collect cells for DNA quantification from the rectal mucosa was investigated. The sensitivity and specificity of this test to detect CRC or any pathology in colon and rectum were ultimately too low to be acceptable. In the second paper, the prognostic value of growth differentiation factor 15 (GDF 15) was evaluated in patients curatively operated for colorectal cancer. GDF 15 expression was demonstrated to be associated with a negative prognosis in patients with stages I-III and III disease. In the third paper, the prognostic value of BRAF, PIK3CA KRAS and MSI was evaluated in a cohort of patients with CRC stratified by disease and recurrence. The results indicated that patients with CRC stage III without recurrence have a higher frequency of BRAF mutation compared to stage III patients with recurrence. In the fourth paper, histopathological predictors of pathologic complete response (pCR) as well as the association between pre-treatment carcinoembryonic antigen (CEA) levels and pCR in non-smoking and smoking patients receiving preoperative chemo-radiotherapy for rectal cancer were evaluated. Only in non-smokers was a low CEA level significantly associated with pCR, suggesting that the predictive value of CEA for pCR in rectal cancer in smokers can be limited. In sum, this research has investigated a new method for CRC detection and further evaluated the clinical use of prognostic and predictive markers in CRC.

Purpose: Given that CRC Screening disparities in people experiencing homelessness has been heavily understudied, the purpose of this study is to assess how existing knowledge and access to resources about CRC screenings affect the ability to obtain CRC screenings in people experiencing homelessness in Central Florida. Methods: In March 2023, a team of researchers surveyed subjects who do not have stable housing in two Central Florida locations: a local shelter and a resource center serving the predominantly unsheltered. The survey assessed current understanding of CRC screenings and available/lacking resources necessary for completing CRC screening in this population. There was a total sample size of 75 participants, with 36 participants from the shelter and 39 from the service center location. Our inclusion criteria included those who are undomiciled, age 45 and over who speak Spanish or English. Results: The results indicate that there is a statistical difference between those who are screened and not screened when assessing provider counseling (p<0.001), awareness of how to get screened (p<0.001) and access to the same medical provider every visit (p=0.0389). In regard to receipt of CRC screening, there were no statistically significant results when assessing demographics and other resource-related factors. Conclusion: Because data was collected in locations that provided resources, this study may not be representative of all undomiciled individuals in Florida, especially in rural areas. Our results imply a need for provider counseling, patient education and access to a primary care provider. More research needs to be conducted from the physician perspective to understand the context of existing barriers to CRC screening.

Despite the evidence that colorectal cancer screening is effective in reducing the incidence of and mortality from colorectal cancer, racial and ethnic disparities in colorectal cancer screening persist in the United States. African-born immigrants in the United States have lower colorectal cancer screening rates than native-born Americans. The purpose of this quantitative, retrospective, cross-sectional study was to examine how family income, health insurance status, language of interview, length of stay in the United States, perceived health status, level of education, and having a usual place for medical care affect colorectal cancer screening among African-born immigrants in the United States. The immigrant health services utilization model provided the framework for the study. Secondary data collected in 2010, 2013, and 2015 through the National Health Interview Survey from 349 African-born immigrants age 40 years and above were analyzed using logistic regression and a chi-square test of independence. A stratified multistage sampling procedure was used to select the sample for the study. Results showed a significant association between colorectal cancer screening and health insurance status, length of stay in the United States, perceived health status, and having a usual place for medical care. However, no association was found between colorectal cancer screening and family income, education level, and interview language. Findings may be used to impact positive social change and guide policy decisions on colorectal cancer preventive interventions targeting African-born immigrants living in the United States.

Background and PurposeGlobally and in the United States (US), colorectal cancer (CRC) is the second leading cause of cancer-related death, following lung cancer. In addition, there are established racial disparities in incidence and mortality for this disease, where ethnic minority groups have higher incidence and mortality rates. Blacks currently have the second-highest rates of CRC incidence and mortality, are diagnosed at more advanced stages, and have the lowest 5-year survival rates of all racial groups. Multiple influences impact this disparity including area- and individual-level factors. Area-level factors, encompassing social determinants of health (e.g. area-level poverty, housing characteristics, etc.), play a role in disease etiology and outcomes. In addition, timely CRC screening (CRCS) reduces CRC incidence and mortality; however, screening patterns, globally and in the US, are not optimal and differ by race, with ethnic minority groups having low CRCS adherence compared to non-Hispanic whites. Differences in CRCS behaviors and outcomes have been noted for Blacks, a term used to describe, for example, a heterogeneous racial group comprised of US-born Blacks and immigrants from Africa and the Caribbean. While CRCS barriers are well documented for the general population, CRCS barriers are less understood for Blacks and very little is known about CRCS habits and CRCS barriers within this heterogeneous racial group, with limited research including Caribbean immigrants and no known research including African-born immigrants. This dissertation uses a mixed-methods approach to describe CRC incidence, advanced stage at diagnosis, and mortality, CRCS behaviors, and CRCS barriers within the heterogeneous Black population in Philadelphia County, Pennsylvania. Aim 1. Assess colorectal cancer incidence, advanced stage at diagnosis, and colorectal cancer mortality, overall and among individuals who identify as Black/African American, and contextual disparities in Philadelphia County utilizing data from the Pennsylvania State Cancer Registry (2010–2016) and relevant US Census and American Community Survey data. Aim 2. Determine colorectal cancer screening adherence for Cancer Prevention Project of Philadelphia (CAP3) participants who self-identify as Black. Aim 3: Conduct gender-specific focus groups to elucidate the principal barriers to colorectal cancer screening adherence within an average-risk group of adults, ages 45–75, who self-identify as Black or African American, in an urban population. Methods Aim 1. Using an ecological design, descriptive, geographic spatial clustering and hierarchical logistic regression analyses were done to describe CRC incidence, advanced stage at diagnosis, and colorectal cancer-specific mortality in Philadelphia County at the individual- and area-level. CRC incidence, stage at diagnosis, and mortality data for histologically confirmed CRC cases were obtained from the Pennsylvania Cancer Registry from 2010 to 2016, with mortality data including deaths through 2020. Area-level data were retrieved from the US Census Bureau, American Community Survey, etc. Individual- and area-level descriptive characteristics were calculated for all CRC incident cases, cases diagnosed at advanced stage, and colorectal cancer-specific mortality, overall and for whites and Blacks. Geographic clusters with higher-than-expected relative risk for each outcome of interest at the census tract level (HRCT) were identified and individual- and area-level descriptive statistics were calculated for Blacks, overall and by HRCT status. Adjusted hierarchical logistic regression analyses using backward stepwise elimination with model quasi-information criterion was performed to identify potential predictors of HRCTs for CRC incidence and advanced stage at diagnosis. Aim 2. Cross-sectional data from age-eligible adults, 50–75 years (N=357) participating in the ongoing CAP3 study was used to measure CRCS prevalence and adherence and region of birth (e.g., Caribbean-, African-, US-born). Prevalence and adherence were based on contemporaneous US Preventive Services Task Force guidelines. Descriptive statistics and adjusted prevalence and adherence proportions were calculated by region of birth. Adjusted logistic regression models were performed to assess the association between region of birth and overall CRCS and modality-specific adherence. Aim 3. To assess CRCS barriers, we conducted six sex-specific focus groups (n=3 female, n=3 male) with individuals, ages 45-75, who self-identified as Black (i.e., US-, Caribbean, or African-born) and were. Focus groups were held in person and via Zoom, recorded and transcribed verbatim. Codes were developed using coding consensus, co-occurrence, and comparison and open, axial, and selective coding rooted in grounded theory. Dedoose was used to determine CRCS barrier themes as well as general and modality-specific barriers by sex and by region of birth. Results Aim 1. In Philadelphia County, there were 4,641 CRC incident cases, of which 2,086 (44.9%) were non-Hispanic Black (NHB), and 2,555 (53.1%) were white. Mean age at diagnosis for CRC incidence (65.0 vs. 68.9 years), advanced stage at diagnosis (63.2 vs. 67.4 years), and colorectal cancer-specific mortality (67.5 vs. 71.7 years) was lower for Blacks compared to whites (p-value<0.001). Blacks were also diagnosed at a more advanced stage (25.0% vs. 22.4%, p-value=0.038) or unknown stage (8.01% vs. 5.64%, p-value=0.001). For each outcome, when compared to whites, higher proportions of Blacks lived in areas with higher proportions of markers of low socio-economic status and lower proportions of CRCS adherence. Geographic clusters at a higher-than-expected risk of CRC incidence were found in Northeast Philadelphia, North Philadelphia, West Philadelphia, and Southwest Philadelphia. Geographic clusters at a higher-than-expected risk of CRC diagnosed at an advanced stage and colorectal cancer-specific mortality overlapped and were in the North, Kensington, and Southwest neighborhoods of Philadelphia. Area-level NHB, the primary independent variable of interest, reduced the odds of HRCT for CRC incidence (OR: 0.971, 95% CI: 0.960, 0.983) and was not significantly associated with HRCT for advanced stage at diagnosis. In addition, after adjustment, for every one-unit increase in the percent of area-level foreign-born Blacks, there was 1.17-increased odds of being a HRCT for CRC incidence (95% CI: 1.07, 1.28). Similarly, there was a significant positive association with area-level foreign-born Black and being in a HRCT for advanced stage at diagnosis (OR: 1.15, 95% CI: 1.05, 1.26). Other area-level variables that were associated with HRCT for CRC incidence were median rent, percent of mortgaged housing units, and per capita income, which reduced the odds of being a HRCT; Percent of mortgaged housing units also reduced the odds of being a HRCT for advanced stage at diagnosis. Further, CRCS adherence reduced the odds of being a HRCT for advanced stage at diagnosis by approximately 15% (OR: 0.849, 95% CI: 0.791, 0.911). Aim 2. Respondents were 69.5% female, 43.3% married/living with a partner, and 38.4% had <$25,000 annual income. Overall, 78.2% reported past CRCS; however, stool test had the lowest prevalence overall (34.6%). Caribbean (95.0%) and African immigrants (90.2%) had a higher prevalence of overall CRCS compared to US-born Blacks (59.2%) (p-value <0.001). African immigrants were five times more likely to adhere to overall CRCS than US-born Blacks (OR: 5.25, 95% CI: 1.34, 20.6). Immigrants had higher odds of being adherent to colonoscopy (Caribbean=OR: 6.84, 95% CI: 1.49, 31.5; African =OR: 7.15, 95% CI: 1.27, 40.3) compared to US-born Blacks. Aim 3. The majority of focus group participants were 60–64 years old and 72% were immigrants (41% African-born, 31% Caribbean-born). Most participants had had CRCS, but 45% were non-adherent to national CRCS guidelines. Overall, lack of knowledge/awareness, fear, and a sense of feeling healthy and subsequently not seeing the need for CRCS emerged as overarching themes to CRCS barriers. General barriers differed by gender: for women lack of physician recommendation or explanation of CRCS was important and for men not knowing anyone with a history of CRCS was commonly cited. .” Differences in modality-specific barriers by gender were also noted. Barriers also differed by region of birth. US-born Blacks described lack of community advocacy promoting CRC and CRCS awareness as a barrier. African-born Blacks expressed lack of routine CRCS and utilization of preventive medicine in their native country as barriers. US- and Caribbean-born Black males, communicated that discussing CRCS was taboo, which was tied to hegemonic masculinity leading to a lack of conversations about CRC and CRCS. The use of traditional home remedies emerged as a barrier given respondents felt these remedies would aid in preventing CRC thereby reducing the need for CRCS. Immigrant Blacks also described limited insurance coverage due to their citizenship status. Conclusions This dissertation provides the first known insight into various outcomes across the colorectal cancer continuum for the heterogeneous Black population including the growing immigrant Black subgroups in Philadelphia County. To reduce CRC incidence and mortality, interventions and resources to increase CRCS uptake need to target geographic locations with higher percentages of foreign-born Blacks, lower CRCS adherence, and areas with worse socio-economic markers. Also, while Black immigrants had higher CRCS adherence compared to US-born Blacks, CRCS is still sub-optimal in the Black population. Further, CRCS barriers exist and differ by gender, and importantly, there are nuanced barriers by region of birth. Thus, efforts to increase CRCS should address the common and unique barriers and promote stool-based testing, as stool test adherence was low and focus group participants were unfamiliar with this modality as it is not widely promoted or available in clinical practice. In short, these findings across the colorectal cancer continuum should be taken into account for resource allocation and when designing targeted or tailored interventions to promote CRCS uptake for the heterogeneous Black population, which would reduce CRC incidence, late-stage diagnosis, and mortality. / Epidemiology

Background: Behavioral interventions and evidence based guidelines along the cancer control continuum can reduce the burden of cancer. Objectives: This dissertation aims to increase our understanding of colorectal cancer screening (CRCS) decisional conflict and breast cancer survivorship care. This project: 1) assesses CRCS decisional conflict in a general population, 2) uses the Theory of Triadic Influence to model and evaluate direct and indirect associations between CRCS decisional conflict and colonoscopy adherence, 3) assesses post-treatment breast cancer care. Methods: Data from a questionnaire administered to randomly selected adults, 50-75 years, living in six MN communities (N=1,268) and the 2010 Behavioral Risk Factor Surveillance System (BRFSS) (N=1,024, women ages 27-99) were used. Multivariable logistic regression was used to identify characteristics associated with high CRCS decisional conflict; then structural equation modelling (SEM) was performed to assess direct and indirect associations of CRCS decisional conflict and colonoscopy adherence. Using BRFSS data, multivariable logistic regression was performed to assess the association between years since diagnosis and the type of clinician providing the majority of care for breast cancer survivors after treatment completion. Results: Greater colonoscopy barriers (OR=1.04; 95% CI: 1.02-1.05) and CRCS-specific confusion (OR=1.12; 95% CI: 1.10-1.15) as well as a healthcare provider not discussing CRCS options (OR=1.67; 95% CI: 1.18-2.37) were associated with increased odds of high CRCS decisional conflict. A similar relationship was found in the SEM analyses: both greater levels of perceived colonoscopy barriers and CRCS confusion were associated with higher decisional conflict (standardized total effects=0.42 and 0.39, respectively, p-values < 0.01). CRCS decisional conflict was associated with increased non-adherence to colonoscopy. This relationship was mediated by CRCS-specific self-efficacy and intention (standardized total effect=0.14, p-value <0.01). Among breast cancer survivors, women 0–1 and 2–3 years since diagnosis were 2.1-2.6 times more likely to have a cancer-related clinician providing the majority of care compared to women 6+ years since diagnosis (95% CIs: 1.0-4.3; 1.4-4.6). Conclusions: Decreasing colonoscopy barriers and CRCS-specific confusion could decrease CRCS decisional conflict and ultimately increase CRCS uptake. National policies to move breast cancer follow-up care to a primary care provider might be well-received by cancer survivors.

Introduction: Shared decision making (SDM) has been advocated as an optimal approach to medical decision-making. Yet, little is known about how patients perceive SDM and whether patient-defined SDM is associated with patient outcomes. Methods: This three-manuscript dissertation used a mixed-methods approach including a systematic literature review and both qualitative and quantitative research methods. The aims were to: (1) systematically review the patient outcomes studied in relation to SDM and identify under what measurement contexts SDM is associated with which types of patient outcomes; (2) use in-depth, qualitative interviews to develop a conceptual model of patient-defined SDM and compare this to recent decisions that patients labeled as shared; and (3) apply the model of patient-defined SDM to the context of colorectal cancer screening. Results: Study 1 found that 39 studies measured SDM and evaluated it with a patient outcome, and only 43% of patient outcomes assessed were significantly associated with SDM. Patient reports of SDM were most likely to be associated with outcomes. Study 2 found that patients’ conceptual definition of SDM included four components: exchange of information, active listening, patient-self advocacy, and a personalized physician recommendation. Patient descriptions of recent decisions labeled as shared ranged from very simple recommendations through complex interactions, with the only commonality among shared decisions being that the patient and physician ultimately agreed. Study 3 found that the most commonly observed component of patient-defined SDM was patient self-advocacy (76%) and least common was a personalized physician recommendation (23%). Only 9% visits contained all four patient-defined SDM components. In adjusted models, physician provision of information around the process and potential side effects of colorectal cancer screening was associated with an increase in screening. There were differences in screening rates by the patient’s initial verbal response to the physician recommendation with those who initially refused being least likely to be screened (40%) and patients who did not verbalize a response to the recommendation being most likely to be screened (70%). Discussion: Findings across the three studies highlight the complexity of studying and measuring SDM and emphasize the importance of the patient’s perspective on SDM.

Background: The current adherence to colorectal cancer screening (CRCS) guidelines is suboptimal. How neighborhood characteristics, e.g., racial residential segregation (RRS), area-level socioeconomic status (SES) and physician composition, affect CRCS adherence are not fully understood. We assessed associations between facility proximity to RRS areas, area-level SES, physician composition, and CRCS adherence. Methods: Data sources included 2013 Minnesota Community Measurement, 2009-2013 American Community Survey, 2012 U.S. and 2012-2013 Washington State Behavioral Risk Factor Surveillance System data, and 2013-2014 Area Health Resource File. Logistic regressions and weighted multilevel logistic regressions were used to assess the association between facility proximity to RRS areas and CRCS adherence, and association between area-level SES, physician composition and CRCS adherence, respectively. Results: Facility proximity to RRS areas was positively associated with low CRCS performance, e.g., facilities located < 2 miles away from Hispanic-segregated areas were 3 times more likely to have low CRCS performance than those at ≥5 miles away (odds ratio (OR): 2.83, 95% confidence interval (CI): 1.29, 6.24). Most area-level SES measures showed negative bivariate associations between deprivation and colonoscopy/overall adherence, and measures such as education had relatively strong associations, although few of fully-adjusted associations remained statistically significant. Further, a one-unit increase in the percentage of gastroenterologists among physicians was associated with 3% increase in the odds of colonoscopy (OR: 1.03, 95% CI: 1.01-1.04) and overall adherence (OR: 1.03, 95% CI: 1.01-1.04) in the rural-metropolitan areas. Conclusions: Developing culturally tailored CRCS programs, increasing percentage of gastroenterologists, and targeting deprived communities may improve CRCS adherence.

Despite indications that colorectal cancer (CRC) screening strategies can decrease mortality and morbidity, screening rates among veterans remains to be low. In the Veterans Affairs (VA), the performance measure for CRC screening is lower than the national standard. This quality improvement (QI) project evaluated the effect of a team-based approach, effective electronic information structures, and the provision of education to nurses and patients in increasing CRC screening rate in primary care from 77% to 85%. CRC screening data were retrospectively collected prior to the start of the project and then compared to screening data 3 months after project implementation. The t test showed a statistically significant increase (p = .009) in CRC screening post intervention. Descriptive analysis was performed to evaluate the knowledge and proficiency of nurses with regard to CRC screening by using pre- and posttest questionnaires. The findings showed that emphasizing the importance of CRC screening among team members as well as appropriately dividing the work was effective in contributing to an increase in CRC screening in primary care. This project contributes to positive social change by increasing the nurses' confidence and proficiency in promoting health and disease prevention among the veterans; decreasing patient suffering; and improving collaboration between providers, nurses, and other departments in the VA primary care.