Mineral density in a proximal femur or spine has been accepted as the basis for diagnosis of osteoporosis. T-score value of -2.5 has been accepted as threshold value. However, it is known that the fracture risk increases with mineral bone density decrease whereas from the other side 75% of fractures occur in a person with T-score higher than -2.5. The calculation of the absolute value of risk of fracture is the solution to that problem. This calculation is based on relative fracture risk index for specific age, known from prospective studies in Sweden. The value of absolute fracture risk for given person is calculated by multiplying known index for age by indexes of relative risk factors existing, e.g. low energy fracture, fracture of proximal femur in mother, smoking, etc. 10% absolute fracture risk in 10 years duration is generally accepted as threshold of therapeutic intervention.