Therefore, the program to increase initial response proficiency can be regarded as very essential. The Republic of Korea annually conducts more than 10 nuclear emergency response training programs, and specialized training courses for initial response are conducted twice several times a year. Materials and Methods: The participants of the initial response training program were evaluated by senior professionals who had over 10 years of experience. The DISASTER Paradigm developed by the National Disaster Life Support Program was used as an index for evaluation. The purpose of evaluation was to identify issues in the current training program through evaluation results over a period of three years. The difference-in-differences method was used to quantitatively analyze the evaluation results. Results: Five indicators of the DISASTER Paradigm demonstrated that personnel skills improved through training. However, three indicators showed that skill levels decreased despite continued training. Conclusion: According to the results, the treatment of radioactive waste (T), evacuation (E), and triage of radiation exposure (R) indicators showed a decrease in the proficiency level, which were difficult to demonstrate in the real world because of the specificity of radiation. Accordingly, program contents corresponding to T, E, and R indicators must be revised using tools that can accurately portray the specificity of radiation.