More Than 70,000 Adventist Health Tulare Patients Affected by Business Associate Breach. A business associate of Adventist Health Tulare has identified unauthorized access to the information of 70,000 patients, and Columbia University Irving A business associate of Adventist Health Tulare has identified unauthorized access to the information of 70,000 patients, and Columbia University Irving Medical Center has discovered patient data has been exposed on the internet. Adventist Health has recently announced that the protected health information of more than 70,000 patients of Adventist Health Tulare in California has been accessed by an unauthorized individual. The security breach occurred at a business associate, Signature Performance, which was used to collect payments for services. Third-party company: Signature Performance.