Factors Associated with False Positive Fecal Immunochemical Tests in Trang Colorectal Cancer Screening Program Population


  • Mookda Nivaarrarsuwonnakul Division of Surgery, Trang Hospital, Trang, Thailand


Fecal immunochemical tests, Colorectal cancer, Screening, False positive


Background and Objective:  Early detection of colorectal cancer (CRC) has emerged as an important global issue. Since 2018, fecal immunochemical tests (FITs) have been offered as a primary screening test for CRC by the Thai National Health Service plan despite their varied accuracy according to various factors. The primary aim of this study was to identify demographic factors associated with false-positive (FP) FIT results in CRC screening in the Trang population. The secondary aim was to report the outcomes of the screening program in Trang Province.

Methods: The data of all 542 participants in Trang with positive FIT tests from the CRC screening program conducted at Trang Hospital between 1 October 2021 and 28 February 2023 were retrospectively reviewed. Of these, 347 with complete colonoscopy studies were analyzed. Patients’ characteristics, colonoscopy findings, and pathologic data were recorded. Univariable and multivariable logistic regression analysis was performed to determine factors associated with FP FIT results.

Results: Among 347 participants who showed positive FIT with complete colonoscopy for CRC screening, 33 participants (9.5%) had advanced colorectal neoplasia (ACRN), and 314 participants (90.5%) had FP FIT results (no ACRN). The participants aged under 65 had a higher rate of FP results than the older age group. Female gender and aged under 65 were two factors associated with false positivity. Multivariable logistic regression showed that age < 65 was the only independent risk factor associated with FP FIT results in multivariate analysis (OR = 2.81; 95% CI 1.24-6.35; p = 0.013).

Conclusion: FP FIT results in the Trang population were relatively high. The age < 65 is a significant factor associated with FP FIT results. This result can be used as a piece of evidence to optimize CRC screening strategies.


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How to Cite

Nivaarrarsuwonnakul M. Factors Associated with False Positive Fecal Immunochemical Tests in Trang Colorectal Cancer Screening Program Population. Thai J Surg [Internet]. 2023 Sep. 30 [cited 2024 Jun. 15];44(3):92-7. Available from: https://he02.tci-thaijo.org/index.php/ThaiJSurg/article/view/264135



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