Which piece of information must be physically included on an x-ray image to verify laterality?

• A. Patient date of birth
• B. Right or left marker
• C. Patient name
• D. Exam date

Answer: (B)

Tracking which side of the body is shown on an image hinges on having a right or left marker clearly visible on the radiograph. This marker serves as the definitive cue for laterality, so clinicians can reliably tell which side is being evaluated. It should be placed within the imaging field before exposure and appear on the final image in a way that cannot be cropped out or obscured, ensuring the side is unambiguous during interpretation and in the patient’s record. Other details like patient name, date of birth, or exam date help with identification and documentation, but they do not convey which side was imaged, making them insufficient for confirming laterality on the image itself.