IIRC this is why HHS and HIPAA regulations specify "all ages over 89" as protected health information for purposes of data deidentification – there just aren't that many people who have lived that long.

It also specifies all date elements for patient-specific events (including treatment) more specific than the year must be removed for deidentification generally.

So "I treated a skier with a broken leg in the last skiing season" is something a doctor can't say? (Skiing season is shorter than a year.)

Actually, giving a year of a winter/summer sport-related accident already provides a shorter window for when the accident has occurred. So should all case reports about such be giving at least a two year long window?