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Updated: Apr 6, 2026

E-Patient Counseling Trial E-PACO: Computer Based Education versus Nurse Counseling for Patients to Prepare for Colonoscopy
Published on: August 1, 2019
Effectiveness of the extended parallel process model in promoting colorectal cancer screening
Wendy C Birmingham1, Man Hung2, Watcharaporn Boonyasiriwat3
1Department of Psychology, Brigham Young University, Provo, UT, USA.
Objective:
Relatives of colorectal cancer (CRC) patients are at increased risk for the disease, yet screening rates still remain low. Guided by the Extended Parallel Process Model, we examined the impact of a personalized, remote risk communication intervention on behavioral intention and colonoscopy uptake in relatives of CRC patients, assessing the original additive model and an alternative model in which each theoretical construct contributes uniquely.
Methods:
We collected intention-to-screen and medical record-verified colonoscopy information on 218 individuals who received the personalized intervention.
Results:
Structural equation modeling showed poor main model fit (root mean square error of approximation (RMSEA) = 0.109; standardized root mean residual (SRMR) = 0.134; comparative fit index (CFI) = 0.797; Akaike information criterion (AIC) = 11,601; Bayesian information criterion (BIC) = 11,884). However, the alternative model (RMSEA = 0.070; SRMR = 0.105; CFI = 0.918; AIC = 11,186; BIC = 11,498) showed good fit. Cancer susceptibility (B = 0.319, p < 0.001) and colonoscopy self-efficacy (B = 0.364, p < 0.001) perceptions predicted intention to screen, which was significantly associated with colonoscopy uptake (B = 0.539, p < 0.001).
Conclusions:
Our findings provide support of the utility of Extended Parallel Process Model for designing effective interventions to motivate CRC screening in persons at increased risk when individual elements of the model are considered. Copyright © 2015 John Wiley & Sons, Ltd.

