The worker, who is no longer affiliated with Northwestern Memorial Hospital, may have accessed 682 patient medical records without an identified professional purpose between Oct. 27 and Dec. 2, according to the newspaper.
The hospital learned of the incident Dec. 2. An investigation found the worker may have viewed patient names, addresses and detailed treatment information, but not Social Security numbers or patient financial information, according to the report.
The hospital said it plans to send letters to affected patients about the incident.