This quantity is characterized by broadband ultrasound attenuation when measuring it using quantitative ultrasound. It doesn’t have to do with lipids, but mutations in LPR5 that control this quantity are present in Van Buchem disease. Age, height, weight, TBS, and this quantity are the main inputs of the FRAX tool. (15[1])Jean Lobstein described a condition in which this quantity is low that often results in blue sclerae. A decrease in this quantity (15[1])is a common side effect of (*) puberty blockers (10[1])and androgen (10[2])deprivation (10[1]-5[1])therapy. (10[3])This quantity is typically measured by DEXA scans. (10[1])Inability (10[1])to form type I collagen leads to this quantity being low in a condition partially called ■END■