Colorectal cancer is the third most common cancer worldwide and it is the second most common factor for death by cancer (
1-
3). The incidence of colorectal cancer, as a main health concern, is increasingly rising in Iran (
4). The timely and proper colorectal cancer screening is a leading factor to reduce incidence and consequences of this disease.
Interventions for disease prevention are designed based on theories of engagement in health behaviors. The extended parallel processing model is a main theory in health behavior change (
5-
7). The extended parallel processing model is based on the belief that when people are afraid of a threat, they take actions to reduce or control those unpleasant scenarios (
7). In the extended parallel processing model, perceived susceptibility is an important motivating factor in many healthy behaviors and disease screening. Perceived susceptibility directly and indirectly influence the attitudes, self-efficacy, and intent to behaviors (
8).
The empowerment in cancer prevention and cancer treatment is the positive, dynamic, and multidimensional concept (
9,
10). The empowerment helps to prevent cancer and it encourages screening to reduce cancer incidence (
11). Health literacy includes the person’s ability to read and interpret the necessary information about health so that they can take appropriate decisions for their health conditions. By interacting collaboratively, Health literacy and empowerment impact the screening, diagnosis, and consequences of cancer (
12-
14). Despite the high rate of deaths from cancer, cancer screening is less than health objectives for 2020 (
15). Lack of cancer-related literacy and knowledge about cancer and cancer screening are among the primary barriers of cancer screening (
16). Fear of cancer and cancer risk perception are main predictors for plans and actions of cancer screening test (
17,
18). On the other hand, the extreme fear of cancer is associated with avoiding cancer screening (
19). The combination of low socioeconomic conditions, poor health, diminished social support, and low health literacy affect the intention to colorectal cancer screening (
20-
22). Race, ethnicity, age, education, income, access to health care, recent meetings with doctors, the use of other screening tests, doctor’s recommendation for testing, and insurance coverage are the main correlates of colorectal cancer screening (
6,
23,
24). Having adequate health literacy is associated with the colorectal cancer screening (
25,
26). Higher self-efficacy, previous participation in cancer screening, and more knowledge about colorectal cancer were known as the independent predictors of a plan to colorectal cancer screening (
27,
28). The lower levels of health literacy and poor socioeconomic status are associated with a higher perception of severity of the disease and medical testing avoidance (
29,
30). Higher perceived risk of colorectal cancer incidence increase engagement in screening tests (
31). In addition, the association between perceived susceptibility and perceived severity with cancer screening mediated by cancer-related literacy (
32). Cancer-related literacy, fear of cancer, and cancer-related empowerment moderate the relationships of self-efficacy, response efficacy, perceived severity, and perceived susceptibility to disease with the cancer screening (
16,
33). Health literacy may empower individuals, which in turn lead to increased understanding of the disease and perform screening tests (
34). Perceived susceptibility is mediated by barriers and perceived self-efficacy and impacts the colorectal cancer screening with the mediation of factors, including fear of cancer and empowerment (
9,
35).
There is no integrated model that can examine the main components associated with colorectal cancer screening. Theoretically, this model has been developed based on the related previous models by Birmingham et al. (
33), Leung, Wong and Chan (
6), Shi and Smith (
8), Leung et al. (
18), and Power et al. (
21). In previous studies, the fear of cancer in the prediction of information seeking and screening intent has been less studied. In addition, although cancer risk and cancer risk perception are expected to be negatively affected by the avoidance of cancer data acquisition, this relationship is not empirically verified. As main gaps in previous studies, lack of attention to the empowerment and health literacy in colorectal cancer screening is another weakness of previous research. This study in the integrated and relatively comprehensive model provides an understanding of the role of health-related empowerment in cancer and health literacy in predicting the screening of colorectal cancer. Finally, this study investigates an exploratory model regarding the distinctive culture of Iran to explain the colorectal cancer screening. Considering the theoretical foundations and the effect of the parallel process model of health-related behaviors, the aim of this study is the prediction of colorectal cancer screening based on the extended parallel processing model with regard to the moderating role of cancer-related literacy and cancer-related empowerment as presented in a hypothetical structural model (
Figure 1).