If the results of a dose calibrator geometric variation test exceed the values by 12-15%, what should the technologist do?

When a dose calibrator shows a geometric variation in its test results exceeding the acceptable values by 12-15%, using a correction factor to determine true activities is the appropriate course of action. This situation suggests that the dose calibrator is potentially measuring inaccurately due to the influence of geometric variance, which can occur when the radioactive source is not positioned ideally within the calibration geometry.

Applying a correction factor allows for accurate quantification of radionuclide activity despite this discrepancy. By adjusting the measured values with a specific correction factor, the technologist enables more reliable assessing of radioactivity levels. This approach ensures that clinical decisions are based on accurate readings, which is crucial in nuclear medicine to ensure patient safety and effective treatment planning.

Other options would not be immediately suitable. Replacing the instrument or having it repaired might be necessary if the problem persists or is due to malfunctions, but that is not the immediate response when a correctable variance is observed. Performing a chi-square analysis is not directly applicable in this context, as the situation requires practical adjustments rather than a statistical evaluation.