When you open a chart through our records gateway, it asks for a verification code: the patient’s four-digit birth year followed by the last two digits of the MRN. People ask why it is that, of all things, and not a real secret.
The answer is that the code is not a secret. It was never meant to be one.
“Break the glass” is the hospital term for emergency access: you are allowed in, but you have to deliberately do something that proves you meant to. The code exists so that nobody opens the wrong chart by accident (a mistyped MRN is the most common way that happens) and so that the audit log records that a person, or an assistant, looked at the patient in front of them. If you know the birth year and you are holding the MRN, you almost certainly have the right patient.
We originally asked for the full date of birth. That turned out to be a problem, because half the clinics store it as MM/DD/YYYY, a third store it as YYYY-MM-DD, and one clinic stores it as the number of days since the founding of the clinic. (I wish I were making that up.) The birth year is the only part everybody agrees on.
Why the last two digits of the MRN? Because the first seven were already on the screen, and a code that is entirely visible on the screen is not a code. It is a reading test.