In a medical context, "DOI" most commonly stands for "Date of Injury". It refers to the specific date when a patient sustained an injury, often used in medical records, insurance claims, and workers' compensation cases to track the timeline of an incident and its treatment.

For example:

• In occupational health, the DOI helps determine the eligibility for compensation or the progression of recovery.
• In clinical settings, it’s used to correlate symptoms or complications with the injury’s onset.