text: According to the Global Consensus Recommendations on Prevention and Management of Nutritional Rickets and the Institute of Medicine (IOM), vitamin D deficiency is classified into two groups of deficient and Insufficient based on serum 25(OH)D level. It could be further classified as mild, moderate, and severe deficiency. Another<unk>  scheme is based on etiology of vitamin D deficiency which classify it as acquired or inherited.
option_0: Vitamin D deficiency classification
option_1: Hyperparathyroidism classification
option_2: Osteoporosis classification
option_3: Osteoporosis classification scheme
option_4: Vitamin D deficiency epidemiology and demographics
option_5: Hypoparathyroidism diagnostic criteria
option_6: Vitamin D deficiency physical examination
option_7: Hypocalcemia classification