Final answer:
The error is most likely a misinterpretation of medical images, where a subdural hematoma is mistaken for a double image of the cranium bone.
Step-by-step explanation:
The error described in the scenario, where a subdural hematoma is mistaken for a double image of the cranium bone, is most likely the result of a misinterpretation of medical images.
The standard algorithm of a patient's head involves reviewing various imaging techniques like CT scans or X-rays to identify abnormalities. In this case, the subdural hematoma may have appeared similar to a double image due to the overlapping of structures or artifacts in the imaging process.