Psychosocial determinants of colorectal screening intention among the Persian Older adults using Parallel extended process model (EPPM)

Abstract Background and objective: Colorectal cancer (CRC) is recognized as one of the most common cancers in Iran and worldwide, with high mortality rate especially among older adults. Screening strategies, especially Fecal Occult Blood Testing (FOBT) followed by colonoscopy, have been proven to significantly reduce CRC mortality. However, despite their proven effectiveness, screening uptake remains low. The present study aimed to determine the factors influencing the colorectal cancer screening intention among the older adults considering Parallel Extended Process Model (EPPM). Method In this cross-sectional study, 355 participants aged 60 or older who attended the urban health centers in Gorgan, Iran, in 2023 were selected using multistage systematic random sampling. Data were collected using pervious validated questionnaires developed based on the EPPM (susceptibility, severity, self-efficacy, response efficacy, fear, defensive mechanism, intention) and knowledge. Validity and reliability of the study tools assessed in the present study before data collection. Results The mean age (SD) was 68.38 ± 6.12 years. The educational level of most participants was less than a high school diploma. In addition, 43% reported having an adequate financial status. A small sample proportion had a family history of colorectal cancer although only 7% had previously undergone colonoscopy. Higher level of knowledge was directly and significantly associated with perceived susceptibility, perceived severity, perceived self-efficacy, and perceived response efficacy. (P < 0.05). Analyzing efficacy pathway indicated that self-efficacy was the most influential factor enhancing participants’ intention to undergo colorectal cancer screening (P < 0.05). However, perceived susceptibility exerted the greatest effect on screening intention in the threat pathway (P < 0.05). Conclusion Older adults with higher self-efficacy demonstrated stronger intentions to undergo colorectal cancer screening. Therefore, interventions based EPPM enhance individuals’ confidence in their ability to perform CRC screening. Furthermore, perceived severity leads to higher intention to perform CRC screening in older adults. Emphasized risk perception is another factor that should be considered in interventional procedure. Certainly, theory driven interventions may enhance participation in CRC screening among older adults.