What is the difference between T-score and Z-score in osteoporosis?
DEXA scores are reported as “T-scores” and “Z-scores.” The T-score is a comparison of a person’s bone density with that of a healthy 30-year-old of the same sex. The Z-score is a comparison of a person’s bone density with that of an average person of the same age and sex.
How do you interpret osteoporosis z-scores?
A Z-score compares your bone density to the average values for a person of your same age and gender. A low Z-score (below -2.0) is a warning sign that you have less bone mass (and/or may be losing bone more rapidly) than expected for someone your age.
What is a normal Z-score for osteoporosis?
A T score between -1 and -2.5 indicates lower than normal bone density for age – this is referred to as osteopenia. A score lower than -2.5 indicates significant bone loss – 25% or more and this is classified as osteoporosis.
What is the main difference between z score and T-score?
The main difference between a z-score and t-test is that the z-score assumes you do/don’t know the actual value for the population standard deviation, whereas the t-test assumes you do/don’t know the actual value for the population standard deviation.
Is it better to have a higher or lower z score?
A high z -score means a very low probability of data above this z -score. Note that if z -score rises further, area under the curve fall and probability reduces further. A low z -score means a very low probability of data below this z -score. The figure below shows the probability of z -score below −2.5 .
What do T scores mean in osteoporosis?
A T-score between −1 and −2.5 indicates that you have low bone mass, although not low enough to be diagnosed with osteoporosis. A T-score of −2.5 or lower indicates that you have osteoporosis. The greater the negative number, the more severe the osteoporosis.
What is a bad z score for osteoporosis?
“Osteopenia(bone mass lower than normal peak bone mass) is below minus one to minus 2.5. Lower than minus 2.5 is osteoporosis.” A negative Z score means you have thinner bones than the average of others in your age group; positive means you have better.
What is a bad Z score for osteoporosis?