Texas Health Harris Methodist Hospital Fort Worth recently began notifying patients who were seen between 1980 and 1990 that sheets of microfiche containing patient data, which had been given to document shredding vendor Shred-it to destroy, were found in a park in May 2013 (h/t DataBreaches.net).

Three other sheets of microfiche, the hospital says, were also found around the same time in two other public areas.

The records on the microfiche may have included patient names, addresses, birthdates, medical records numbers, clinical information, health insurance information, and some Social Security numbers.

The hospital began sending letters to potentially affected patients on July 11, 2013.

"To help prevent something like this from happening in the future, Texas Health Fort Worth and the entire Texas Health System has changed document destruction vendors," the hospital said in a statement. "Shred-it assured Texas Health Fort Worth it has taken appropriate actions as a result of the incident. Texas Health Fort Worth deeply regrets any inconvenience to its patients."