Ask for the patient's full name, the location, and the date, and note the exact response. A common practice is to substitute full documentation of the mental status exam with brief phrases such as "alert and oriented" or "alert and oriented to person, place, and time"—abbreviated as "A&O×3." Given realistic time constraints, it is probably reasonable in non-neurologic patients with normal mental status to write "A&O×3," as long as the meaning is clear. For patients with compromised mental status, however, it is very important to document specifically the questions they were asked and how they answered. This is really the only way to detect changes in a patient's mental status when different doctors are following a patient. For example, for the orientation section on a patient Harry Smith, you should write the following:
Name: "Harry Smith"
Location: "Hospital," but does not know which one
Date: "1942," and does not know month, date, or season
You should never write instead: "The patient was A&O×2," since this is ambiguous and makes it hard to know what the patient's true mental status was at the time of the exam.
The main usefulness of this set of questions is that it is so standard. It tests mainly recent and longer-term memory (see below), but as in all other parts of the exam, the response is also influenced by level of alertness, attentiveness, and language capabilities.