What is considered normal BMD according to T-score definitions?

• A. T-score between -1 and -2.5 SD
• B. T-score below -2.5 SD
• C. T-score better than -1 SD
• D. T-score above +1 SD

Answer: (C)

Normal bone mineral density is defined by a T-score of -1.0 or higher when compared to a young healthy reference population. The T-score shows how many standard deviations your BMD is from that young adult mean. Therefore, a T-score between -1.0 and above is considered normal, which is what “better than -1 SD” conveys. A T-score from -1 to -2.5 SD indicates osteopenia, and below -2.5 SD indicates osteoporosis. A T-score above +1 SD is possible and still falls within normal, but the standard cutoff used for defining normal is -1.0 or higher, making the statement about being better than -1 SD the correct description.