A Methodological and Survival Comparison of NCDB and SEER Database for Colon Cancer Research

Despite differences in sampling techniques and follow-up reporting, NCDB and SEER demonstrated remarkable consistency in survival trends across colon cancer stages and locations. Recognizing these database-specific variations is essential for researchers conducting population-based survival analyses and selecting the most suitable registry for their studies. WHAT DOES THIS PAPER ADD TO THE LITERATURE?: This study provides a comprehensive comparison of NCDB and SEER, highlighting how differences in sampling methodologies, follow-up reporting, and patient representation influence overall survival estimates in colon cancer. It clarifies why prior studies report conflicting survival trends and offers a methodological framework for researchers selecting the most appropriate database for their analysis.