What is the mean value of the T-score statistic?

• A. 25
• B. 0
• C. 50
• D. 100

Answer: (C)

The T-score is a statistical measure used in bone densitometry to compare an individual's bone mineral density (BMD) to the average BMD of a healthy population of the same age and sex. The mean value of the T-score statistic is conventionally set to 0. This is because the T-score is derived from the population mean; hence, a score of 0 indicates that the individual's BMD is equal to the average BMD of the reference group.

A T-score above 0 signifies that the individual's bone density is greater than the mean, while a T-score below 0 indicates lower bone density compared to the average. In medical contexts, particularly in assessing the risk of osteoporosis, the T-score allows clinicians to identify individuals who are at higher or lower risk for bone-related fractures.

Understanding the mean value of the T-score being set at 0 is crucial for interpreting individual scores within the framework of osteoporosis risk assessment.