This study is to find out evidence for selection criteria of additional diagnostic RAI whole-body scan in patients with differentiated thyroid cancer (DTC) who had total thyroidectomy with 131I remnant ablation and first RAI therapy.

Firstly, domestic trend of patients with thyroid cancer and treatment in recent 5 years (Jul 2009 to Jun 2014) was identified through analysis on the National Health Insurance Claims Data Korea.

Secondly, we found the rate of unnecessary diagnostic RAI whole-body scan and developed a predictive model for selection of additional diagnostic RAI whole-body scan based on the retrospective chart review data.