The primary test used to evaluate bones is the DEXA (or DXA) scan, which stands for dual-energy X-ray absorptiometry. It measures bone density and compares it to a young adult population of the same gender and ethnic background — called a reference population — to calculate a T-score, which HCPs then use to diagnose osteoporosis. Other machines, such as ultrasound, particularly at the heel; traditional X-rays; and computed tomography (CT) scans, have the ability to measure bone health, but diagnoses aren't made from these images.