Objective: To compare the participation rate between CT colonography (CTC) and colonoscopy in screening population in randomized controlled trials (RCTs).
Methods: A search was performed using the PubMed, Web of Science, and Cochrane databases. RCTs that included screening populations and reported participation number were assessed. Cochrane risk of bias tool was used to assess the bias and quality. Risk ratio (RR) was used to present the results. The non-participation rate was analyzed to verify the results of participation rate.
Results: Five of 760 studies, with a total of 15,974 invitees, were included. The participation rate was higher at CTC (28.8%) than colonoscopy (20.8%), although the difference did not reach statistical significance (RR = 1.26; p = 0.070; I2 = 90.3%). The non-participation rate at CTC was significantly lower than colonoscopy (RR = 0.92; p = 0.012; I2 = 86.7%). Subgroup analysis suggested both the participation and non-participation rate were with significant difference between reduced/no cathartic preparation CTC and colonoscopy. Cumulative meta-analysis showed both the participation rate and non-participation rate exhibited a trend over time and sample size.
Conclusion: The participation rate was higher at CTC than colonoscopy, although the difference did not reach statistical significance. But the non-participation rate was with statistical difference. Screening population seemed more likely to participate the reduced/no cathartic preparation CTC. Statistical evidence was provided for more large RCTs are needed in the future.
Advances in knowledge: The screening populations seem more likely to participate in the CTC, especially the reduced/no cathartic preparation CTC. The statistical evidence was provided for more large RCTs are needed in the future.