Problem
Describe how the Dual X-Ray Absorptiometry (DEXA) machine measures bone mineral density, percent body fat and body composition. Include in your answer exactly how the scanner works, which patient populations should have a periodic DEXA scan, which patients should not have a DEXA scan, patient preparation issues, safety aspects (e.g., radiation exposure), sources of error, what the research tells us about DEXA scans of different patient populations (e.g., ethnicity differences, height/weight differences, body composition differences of kids vs. adults) and which 2-4 companies currently make and sell DEXA scanners. Discuss all aspects of DEXA and reference your answer. This is the "long answer" question of this lab exercise.