Defense Date


Document Type


Degree Name

Doctor of Philosophy



First Advisor

Resa M. Jones, MPH, PhD

Second Advisor

Pamela J. Mink, PhD, MPH

Third Advisor

Juan Lu, PhD, MPH, MD

Fourth Advisor

Levent Dumenci, PhD


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.


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