A medical report was a report that detailed the medical status of a patient after being examined by a medical practioner, and likely the treatment one received for the ailment. It was typically prepared by the medical staff and was made available to senior officers, and was stored in the patient's medical file or crew report.
Doctor Phlox read every medical file of the crew on board Enterprise and remembered in a conversation with Hoshi Sato the medical record of Malcolm Reed which listed his allergies, including oak pollen, dust mites, tropical grasses, and bromelain. (ENT: "Silent Enemy")
In 2369 Doctor Julian Bashir ordered Nurse Jabara to pull up Chief Miles O'Brien's neurophysiological history, part of his medical report, to find an explanation for his strange behavior caused by the aphasia virus. (DS9: "Babel")
To confirm that Aamin Marritza suffered from Kalla-Nohra Syndrome instead of Pottrik Syndrome, Julian Bashir crosschecked the Bajoran and Federation medical records in 2369. Later, at the request of Constable Odo, Doctor Bashir checked the personal medical history of Aamin Marritza through a subspace link Odo established to Kora II. (DS9: "Duet")
Medical reports can be prepared to only show data from specialized scans. The Doctor performed neurological scans of Tom Paris after Banean memory engrams were integrated into his brain and the results were part of neurological reports that Tuvok referred to later on. (VOY: "Ex Post Facto")
The Doctor's report on the conditions of Chakotay and Captain Kathryn Janeway after being infected with a disease from an unnamed planet lead to Janeway's order to leave Chakotay and her on the planet. (VOY: "Resolutions")