Final answer:
The diameter of the ROI in CT noise assessment should represent 20% of the total diameter, with measurements not exceeding a deviation of +/- 3% or +/- 20 HU. Increasing the sample size can lower sampling error, and the acceptable maximum error is within 3 percent, corresponding to the CI of 18% to 22%.
Step-by-step explanation:
The diameter of the Region of Interest (ROI) in a CT noise assessment should represent a specific percentage of the total diameter of the scanned object. Based on the Confidence Interval (CI) provided, (0.18, 0.22), and the Error Bound Margin (EBM) of 0.02, it can be inferred that the diameter of the ROI should represent 20% of the diameter of the scanned object. Numbers must not deviate more than +/- 3% or +/- 20 Hounsfield Units (HU). When it comes to lowering the sampling error, one method is to increase the sample size, as mentioned in point d.
Moreover, the stated ± 3 percent represents the maximum error bound. This reveals a reporting of a maximum error of 3 percent, meaning that the estimated value should fall between 18 percent and 22 percent. This aligns with the given Confidence Interval (CI).