Supplementary Files 1–17 and analysis code for: Nodal burden identifies where adjuvant radioiodine still improves survival in differentiated thyroid cancer

This record contains the derived analytic outputs (Supplementary Files 1-17) and the complete analysis code for the study "Nodal burden identifies where adjuvant radioiodine still improves survival in differentiated thyroid cancer".The study analysed 63,158 patients with differentiated thyroid cancer treated by total thyroidectomy in SEER Research Data, 17 registries (November 2025 submission), diagnoses 2004-2013, of whom 36,423 received adjuvant radioiodine and 26,735 did not.

Methods comprised overlap weighting, a causal survival forest, sequential landmark analysis and a negative-control (other-cause mortality) outcome.Contents: Supplementary Files 1-4 and 16 (supplementary tables); Supplementary Files 5-14 and 17 (supplementary figures); Supplementary File 15 (supplementary methods, including the full covariate specification, the nodal denominator audit and the propensity-score audit); the figure source-data workbook; the STROBE and TRIPOD checklists; and the R and Python scripts that generate every reported estimate.No individual-level SEER records are included in this deposit.