In bone densitometry, which aspect is less important for serial monitoring?

• A. Standard deviation
• B. Precision
• C. Accuracy
• D. Patient history

Answer: (C)

In the context of bone densitometry, accuracy refers to how close a measured bone mineral density (BMD) value is to the true value. While accuracy is fundamental for a single measurement to be reliable, it becomes less critical in the context of serial monitoring—where the focus shifts to assessing changes in BMD over time.

For serial measurements, the primary concern is the ability to consistently reproduce results within a narrow range. This requires high precision, which ensures that repeated measurements yield similar results under unchanged conditions. Standard deviation serves as an indicator of this precision, as a lower standard deviation signifies more reliable and reproducible measurements over time.

Patient history can also provide valuable context for monitoring changes and guiding treatment decisions, but it does not directly impact the measurement itself. In serial monitoring, the primary goal is to identify trends and changes rather than to ensure each individual measurement is perfectly accurate. Therefore, while accuracy is important in the overall diagnostic process, it is less critical when it comes to evaluating changes in patient BMD over time.