Converting self-reported body weight and height into measured values

Boys age 13-20 years
Measured_body mass (kg) = 0.9839 x Self-reported_body mass (kg) + 0.0861 x age (years) (±2.6455)
Measured_height (cm) = 0.9590 x Self-reported_height (cm) + 0.1938 x age (years) + 3.8458 (±2.3951)

Girls age 13-20 years
Measured_body mass (kg) = 0.9740 x Self-reported_body mass (kg) + 0.1210 x age (years) (±3.1251)
Measured_height (cm) = 0.9428 x Self-reported_height (cm) + 9.4831 (±2.5405)

Men age 64-90 years
Measured_body mass (kg) = 0.9991 x Self-reported_body mass (kg) (±3.639)
Measured_height (cm) = 0.9976 x Self-reported_height (cm) (±3.5833)

Women age 64-94 years
Measured_body mass (kg) = 1.0166 x Self-reported_body mass (kg) (±3.5631)
Measured_height (cm) = 31.4867+ 0.7874 x Self-reported_height (cm) (±3.3778)