A preparatory report was a report created by a Starfleet ship's physician prior to an away mission in order to advise them on what actions to take and avoid while there.
In 2373, The Doctor complained that five away team members had ignored his preparatory reports in as many weeks. These included B'Elanna Torres eating a salad, despite The Doctor warning that Klingons lacked an enzyme for metabolizing a planet's vegetation. The report had warned her not to eat the vegetables. He wondered aloud if he ought to continue issuing the reports. (VOY: "Darkling")