Background: Left ventricular ejection fraction (LVEF) measurements by echocardiography are subject to problems such as low interobserver reproducibility, which depends on the skill of the observer, and variations in measurement technique. Objective: We investigated the reproducibility of echocardiography by comparing the measurement results of a certified sonographer with those of control students. Methods: A total of 30 subjects, 22 adult students and 8 staff members of Shubun University, were included in the study. Measurements were performed according to the standard protocols of the Japanese Society of Echocardiography. Results: LVEF values were significantly lower with the modified Simpson method than with the Teichholz method (M-mode and B-mode) for both the sonographer and students; there was no difference between the M-mode and B-mode approaches for the sonographer, but B-mode was significantly lower for students. Comparing the sonographer and students, there was no significant difference with the M-mode approach, but students had significantly lower values with the B-mode and modified Simpson methods. Although the modified Simpson method is currently recommended for LVEF measurement, the lower values obtained by students using this method are primarily attributed to their inexperience with the measurement technique. Conclusions: In the future, the evaluation of cardiac function by echocardiography will require reproducibility that does not rely on the skill of the observer, and the adoption of echocardiography methods incorporating artificial intelligence is anticipated.

The authors have declared no competing interest.

This study did not receive any funding

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

Ethics committee/IRB of Shubun University Faculty of Medical Science (approval number: Medical Sciences R06-001) waived ethical approval for this work

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