Predictors of colorectal cancer screening intention among Iranian adults: an application of the preventive health model
JPMH - Vol 59, No 2 (2018)


Colorectal Neoplasms
Preventive Health model


Objective: Colorectal cancer is the third most common cancer among adults in Iran. Colorectal cancer screening is the effective way in reducing deaths from this cancer. However, the screening rate of colorectal cancer is very low among Iranian adults. This study investigated predictors of Iranian average-risk adults ' intention to take up colorectal cancer screening with fecal occult blood test using a mediator model.

Methods: Participants of this cross-sectional study were comprised of 478 average-risk adults who were selected using a national sampling frame in Hamadan city, west of Iran. The data gathering instrument was a questionnaire based on the preventive health model constructs. Structural equation modeling (SEM) was employed to test the relationship using Smart PLS 2.0 software

Results: All measures were robust in terms of its reliability and validity. Benefit (b= 0.12, p<0.01), self efficacy (b= 0.36, p<0.01), social support (b= 0.12, p<.05) and barriers (b= -0.14, p<.01) predicted the intention to be screened for CRC. Self efficacy partly mediated effects of social support and perceived barriers on intention. The study model explained approximately 24% of the variance in CRC screening intention with fecal occult blood test

Conclusion: Our findings indicated that the preventive health model constructs such as self efficacy, social support and barriers are useful in understanding CRC screening intentions and can help health planners in developing effective interventions for encouraging Iranian adults to undergo CRC screening.


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