A six-item questionnaire was administered to LUS imaging experts (three emergency medicine specialists and three intensivists) regarding normal lung findings and five pathologic findings—atelectasis, pneumothorax, pulmonary edema, pneumonia, and pleural effusion—made by using the phantom. For each question, six videos of the simulated findings were displayed on the screen, and the rater was asked to select the answer for the specific situations (Fig 2; Video 1). Rater agreement on the phantom for LUS was 100% for 36 questions. Every rater answered all six questions correctly. Table 1 shows the questions, answers, and agreement rates. Individual scores for normal and pathologic conditions in LUS were excellent, and interrater agreement was also excellent.