Purpose: American Indian (AI) women have lower rates of cancer, but later stages of diagnosis and higher mortality than the US general population. We hypothesized that mediators found within different theoretical models of health behavior differentiate women who adhere to mammographic screening guidelines from those who do not. Such mediators may be useful in the design of interventions to increase adherence.

Experimental Procedures: As a community-based participatory research project, tribal health, Indian Health Service representatives, and community representatives worked with the Mayo Clinic team to design a survey derived from 53 interviews with documented adherent and non-adherent women from one Bemidji Area tribe. The survey explored demographic characteristics and six theoretical mediators: Health Literacy, Social Networks, Planned Behavior, Social Norms, Social Support, and Health Beliefs. The survey was mailed to 1200 women with the goal of obtaining 600 responses. Women completing the survey were provided a modest gift card through an impartial third party who not know their names or responses. Responses were analyzed using Fisher's Exact Test or the Chi-square test where appropriate.

Summary of Data: To date, we have achieved a 30% response rate (91 self-described non-adherent and 91 self-described adherent breast cancer screening (mammography) respondents). Mediators from the six theoretical models and demographic features do differentiate AI adherent and non-adherent screeners and may be useful for developing interventions to expand screening adherence. Among significant differences were the following with which adherence associates: (1) Demographic (≤0.01): being married, full-time employed, living at greater distances from health care facility, surgical menopause, and having had a breast biopsy. (2) Health Literacy (≤ 0.001): accurate conceptual understanding of annual mammogram, ultrasound, and family history as a risk factor. (To accommodate the survey format, we replaced the usual measures of health literacy (Short Test of Functional Health Literacy and Rapid Estimate of Adult Literacy in Medicine) for understanding of basic breast screening and breast cancer concepts.) (3) Social Networks (≤ 0.03): having mothers who have encouraged good health. (4) Planned Behavior (≤ 0.001): behavioral beliefs, and intentions. a.) Behavioral Beliefs : looking forward to getting my mammogram; getting my scheduled mammogram rather than accepting an invitation to be with friends; viewing my mammogram as very important. b) Intentions: expecting to screen in each of the next five years, and getting my next mammogram when it is scheduled. (5) Social Norms (≤ 0.001): role of family as a positive influence on my life. (6) Social Support (≤ 0.001): availability of family to comfort one in times of worry. (7) Health Beliefs (≤ 0.001): discounting physical limitations and exam discomfort as justifications for avoiding screening and believing there are no justifications for avoiding mammogram; knowing: how to prepare for a mammogram, what happens during the mammogram process, knowing a mammograms importance, knowing what to do if one feels something unusual in the breast, and knowing someone who has been diagnosed with breast cancer.

Conclusions: No single theoretical model appears to differentiate adherent from non-adherent screeners, but mediators associated with each of the various models do differentiate these screeners. These differentiating mediators should be considered for how they might guide development of interventions to improve screening behavior. The self-report nature of the survey demands that results be considered as tentative and limited, in any case, to the respondents of this tribe.

Citation Format: Wesley O. Petersen, Ann M. Nicometo, Corinna Sabaque. Do demographic characteristics and theoretical mediators of health behavior differentiate American Indian adherent mammographic screeners from non-adherent screeners? [abstract]. In: Proceedings of the Eighth AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 13-16, 2015; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2016;25(3 Suppl):Abstract nr B98.