One- versus two-sample fecal immunochemical testing for colorectal cancer screening: a systematic review and meta-analysis of participation, diagnostic performance, and cost-effectiveness

Li Ye; Qiu Ling Hou; Haijun Peng; Qiu Yang

doi:10.1186/s12876-026-04954-8

One- versus two-sample fecal immunochemical testing for colorectal cancer screening: a systematic review and meta-analysis of participation, diagnostic performance, and cost-effectiveness

BMC Gastroenterol. 2026 Jun 16. doi: 10.1186/s12876-026-04954-8. Online ahead of print.

Authors

Li Ye¹, Qiu Ling Hou¹, Haijun Peng², Qiu Yang³

Affiliations

¹ Department of Gastroenterology, The First People's Hospital of Guangyuan, Guangyuan, 628000, China.
² Ziyang Hospital of West China Hospital of Sichuan University, Ziyang Central Hospital, Ziyang, 641300, China. penghj@ihep.ac.cn.
³ Department of Cardiology, Affiliated Hospital of North Sichuan Medical College, Nanchong, 637000, China. yangqiu@ihep.ac.cn.

PMID: 42298417
DOI: 10.1186/s12876-026-04954-8

Abstract

Background: Whether collecting one or two fecal samples for immunochemical testing (FIT) optimizes colorectal cancer screening outcomes remains unclear.

Methods: We systematically searched multiple databases until October 2025 for studies directly comparing 1-FIT and 2-FIT strategies. Pooled risk ratios (RRs) with 95% confidence intervals (CIs) were calculated for dichotomous outcomes.

Results: Five studies (n = 45,888) and three economic evaluations were included. Participation was higher with 1-FIT (RR = 1.05, P < 0.0001), while 2-FIT had a higher positivity rate (RR = 0.65, P < 0.0001). Although 2-FIT detected more CRC (RR = 0.62, P = 0.02), advanced neoplasia and advanced adenoma detection were similar. The 2-FIT strategy had higher sensitivity (RR = 0.64, P = 0.04) but lower specificity (RR = 1.70, P < 0.001) than 1-FIT. A pivotal finding was that the 1-FIT strategy demonstrated a superior positive predictive value (PPV) for both advanced neoplasia (RR = 1.21, P = 0.004) and advanced adenoma (RR = 1.41, P < 0.0001), which translated into a substantially lower demand for colonoscopy (RR = 0.64, P < 0.0001) Economic evaluations consistently favored 1-FIT across different healthcare systems.

Conclusion: Although the 2-FIT strategy improves test sensitivity, it fails to enhance advanced neoplasia detection while substantially increasing colonoscopy demand due to its reduced positive predictive value. In contrast, the 1-FIT strategy preserves screening efficacy with superior participation rates, resource utilization, and cost-effectiveness. We recommend 1-FIT as the preferred strategy in settings with constrained colonoscopy resources, while reserving 2-FIT for resource-abundant environments where maximizing sensitivity justifies the additional economic and operational costs (Scheme 1).

Trial registration: The research protocol was prospectively registered in the PROSPERO registry, bearing the registration identifier CRD420251153202.

Keywords: Colorectal cancer screening; Cost-effectiveness; Diagnostic accuracy; Fecal immunochemical test.

Publication types

Systematic Review