en Medical Physics Medical Physics تحقيق بديع Original Research Background: Although nuclear technology has various beneficial, it also has a variety of risks. In particular, initial response is very import to respond to risks. <div style="text-align: justify;">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.</div> Nuclear emergency, initial response training, difference-in-differences method. 715 721 http://ijrr.com/browse.php?a_code=A-10-2055-57&slc_lang=en&sid=1 S. Cha 7900319475328460017370 7900319475328460017370 Yes Korea Institute of Radiological & Medical Science (KIRAMS), Seoul, South Korea S.T. Kim 7900319475328460017371 7900319475328460017371 No Korea Institute of Radiological & Medical Science (KIRAMS), Seoul, South Korea S. Song 7900319475328460017372 7900319475328460017372 No Korea Institute of Radiological & Medical Science (KIRAMS), Seoul, South Korea M.D. Yu 7900319475328460017373 7900319475328460017373 No Korea Institute of Radiological & Medical Science (KIRAMS), Seoul, South Korea M. Pak 7900319475328460017374 7900319475328460017374 No Korea Institute of Radiological & Medical Science (KIRAMS), Seoul, South Korea S. An 7900319475328460017375 7900319475328460017375 No Korea Institute of Radiological & Medical Science (KIRAMS), Seoul, South Korea Y.W. Jin 7900319475328460017376 7900319475328460017376 No Korea Institute of Radiological & Medical Science (KIRAMS), Seoul, South Korea C. kim 7900319475328460017377 7900319475328460017377 No Department of Science & Technology Policy (STP), Hanyang University, Seoul, South Korea M. Cho 7900319475328460017378 7900319475328460017378 No Korea Institute of Radiological & Medical Science (KIRAMS), Seoul, South Korea