**Core Concept**
Calibration of examiners is a crucial step in ensuring the reliability and validity of high-stakes medical exams like NEET PG, USMLE, and AIIMS. It involves standardizing the examiner's scoring and feedback to ensure consistency across different sessions and examiners.

**Why the Correct Answer is Right**
Calibration of examiners aims to reduce inter-rater variability by establishing a common benchmark for scoring. This process involves comparing the examiner's scores with a gold standard or a calibrated examiner to ensure that they are providing accurate and consistent feedback. By calibrating examiners, the exam administrators can ensure that the scores are reliable and comparable across different sessions and examiners. This is particularly important in high-stakes exams where the scores can have a significant impact on the candidate's career.

**Why Each Wrong Option is Incorrect**
**Option A:** Calibration of examiners is not primarily aimed at improving the examiners' knowledge of the subject matter. While examiners should have a good understanding of the subject, calibration is focused on standardizing their scoring and feedback.
**Option B:** Calibration of examiners does not involve training them on specific exam questions or content. Instead, it focuses on standardizing their scoring and feedback to ensure consistency.
**Option C:** Calibration of examiners is not a one-time process; it is an ongoing process that requires regular calibration to ensure that examiners continue to provide consistent and accurate feedback.

**Clinical Pearl / High-Yield Fact**
To ensure the reliability and validity of high-stakes medical exams, calibration of examiners is a crucial step that involves standardizing their scoring and feedback to ensure consistency across different sessions and examiners.

**Correct Answer: C. Calibration of examiners is an ongoing process that requires regular calibration to ensure that examiners continue to provide consistent and accurate feedback.**