FSTL3/LTBR protein level ratio in blood (OBA_2054184) can be described as follows. A compound attribute that is the ratio of amount of follistatin-related protein 3 (human) in blood to amount of tumor necrosis factor receptor superfamily member 3 (human) in blood. Also known as: the ratio of amount of follistatin-related protein 3 (human) in blood to amount of tumor necrosis factor receptor superfamily member 3 (human) in blood.