Fig. 1From: Spatially varying effects of predictors for the survival prediction of nonmetastatic colorectal CancerDetails of the patient data screening procedure. For all SEER research data reported from 1973 to 2013, we first considered patients who were diagnosed with primary colorectal cancer after 2004 and who were actively followed-up with case reports from hospital inpatient departments, radiation treatment centers, laboratories, and physicians’ offices and for whom survival times were longer than 1 month; these criteria yielded 249,665 patients. We then excluded patients whose tumor grading and differentiation codes were of undetermined cell types or were not stable or not treated, reducing the number of patients to 211,292. We next excluded patients whose tumor size, lymph nodes, positive regional nodes and examined regional nodes were either NA or unknown, further reducing the sample to 164,331 patients. Finally, we excluded patients with metastases and patients for whom the exact tumor size and number of positive regional nodes were unknown. We ultimately obtained 128,061 patients from 18 SEER registries as our study cohortBack to article page