WHO.html


World Health Organization (WHO) Criteria for the diagnosis of Osteoporosis WHO Technical Report Series. Geneva: WHO, 1994
Normal	Bone density no lower than 1 SD below the mean for young-adult women (T-score greater than or equal to -1)
Osteopenia	Bone density between 1 and 2.5 SD below the mean for young-adult women (T-score greater than -2.5 and less than -1)
Osteoporosis	Bone density at least 2.5 SD below the mean for young-adult women without fractures (T-score less than or equal to -2.5 )
Established Osteoporosis	Bone density at least 2.5 SD below the mean for young-adult women with history of fragility fracture (T-score less than or equal to -2.5 )
What is T-score? T-score is the number of standard deviations the patient's BMD is above or below the average BMD of young adult reference population. T-score = (BMDpatient-BMDyoung-normal-reference)/SDyoung-normal-reference. T-scores are used for the diagnosis of normal BMD, osteopenia or osteoporosis.