### INTRODUCTION

### METHODS

### Participants

^{2}. We categorized ages into five age groups with 10-year intervals between 20 and 70 years old: younger than 30 years old, 30 to 39 years old, 40 to 49 years old, 50 to 59 years old, and older than 60 years. We also classified BMI as four categories with 5 kg/m

^{2}intervals between 15 and 40 kg/m

^{2}: lower than 20 kg/m

^{2}, 20 to 25 kg/m

^{2}, 26 to 30 kg/m

^{2}, and over 30 kg/m

^{2}. Then, we made a target enrollment table with five age groups and four BMI groups, totaling 20 categories of each age and BMI category, and tried to enroll at least one man and one woman in each category. Based on this enrollment target, we finally included 40 subjects (20 men and 20 women). Subjects who had a history of chronic or systemic diseases such as diabetes were excluded. Subjects with any medical histories that could affect their mobility and body composition, including osteoporosis and fracture, and, subjects having recent intentional weight loss or taking any medication that could affect body composition properties were also excluded. All participants provided informed consent. This study was approved by the Seoul National University Bundang Hospital Review Board (IRB No.: B-1704-390-007).

### Measurement of anthropometric and biochemical parameters

### DXA scans and data analysis

### Statistical analysis

*t*test. Differences were considered significant when the

*P*value was <0.05. For each value, a linear regression model between the two machines was calculated. Each regression equation is shown as ‘Hologic Horizon=slope×GE Lunar Prodigy+intercept.’

*t*test were used to compare the baseline characteristics between the male and female participants. Pearson correlation analysis was used to identify whether the difference between the Hologic Horizon and GE Lunar Prodigy DXA measurements was correlated with other variables.

### RESULTS

### Baseline characteristics of the study participants

^{2}, respectively. Systemic blood pressure, weight, height, high density lipoprotein, alanine transaminase and creatinine levels differed significantly between the male and female participants (

*P*=0.005,

*P*=0.002,

*P*<0.001,

*P*=0.027,

*P*=0.030, and

*P*<0.001, respectively), but the other parameters were similar between the sexes.

### Comparisons of body composition measurements by Hologic Horizon and GE Lunar Prodigy

*P*<0.001 in men; and

*P*=0.002,

*P*=0.005, and

*P*<0.001 in women, respectively). The differences between the two instruments were greater in men than in women (Supplemental Fig. S1). Trunk fat mass and trunk lean mass values did not differ between the two DXA devices for either men or women.

^{2}(Fig. 2A). It showed similar pattern with body fat percent (%), and differences between two systems were greater in subjects with either higher or lower body fat percent (%) (Fig. 2B).

### Development of equations to allow conversion of body compositional parameters between GE Lunar Prodigy and Hologic Horizon

*R*

^{2}values were all above 0.9, except for the equation for trunk lean mass in men.

### DISCUSSION

*vice versa*.