Target trial emulation studies in oncology: a comprehensive analysis

Background: Target trial emulation (TTE) has emerged as an important framework for generating comparative effectiveness real-world evidence. However, the methodological characteristics and clinical utility of this framework in oncology remain insufficiently characterized. This study systematically evaluated the characteristics of oncological emulation studies. Materials and methods: We systematically searched PubMed, Embase, and Web of Science Core Collection databases from inception to December 22, 2023, to identify oncology-focused TTE studies. Study characteristics, TTE components, and consistency with corresponding randomized controlled trials (RCTs) were analyzed. Categorical variables were summarized as frequencies and percentages and compared using Chi-square tests in SPSS (version 27.0), with P-values <0 .05 considered statistically significant. Results: A total of 54 TTEs were included. Most were conducted in the United States (22, 40.7%), and publications peaked in 2023 (17, 31.5%). Colorectal cancer (13, 24.1%) was the most frequently investigated cancer type. Studies predominantly used data from national databases (18, 33.3%). While all studies prospectively specified the target trial protocol and emulation procedures, only 1 (1.9%) study was prospectively registered, and most emulation studies (48, 88.9%) did not reference a reporting guideline. Among the 10 RCT-TTE pairs available for comparison, 6 (60.0%) pairs achieved agreement in both statistical significance and effect estimates. Conclusion: This study provides a comprehensive analysis of TTE studies in oncology, highlighting their value for generating higher-quality real-world evidence. Future efforts should prioritize prospective protocol registration and standardize reporting to enhance the credibility and reproducibility of emulation studies.