Djossou HJ, Tazi MA, Ghassem MA, et al. - This study was attempted to explore the reproducibility of total and regional body composition in patients with rheumatoid arthritis (RA) and with ankylosing spondylitis (AS) and to compare them to healthy individuals. Researchers enrolled 80 individuals including 32 healthy individuals, 31 RA patients, and 17 AS patients. They evaluated reproducibility through the coefficient of variation, the least significant change, the intraclass correlation, and the smallest significant difference. The outcomes of this research illustrated that the total body tissue mass, fat mass (FM) percentage, FM, lean mass (LM), and bone mineral content (BMC) measurements obtained by dual-energy x-ray absorptiometry are highly reproducible in RA and AS.