our leadership team

Dr. John Blair
A. John Blair, III, MD, F.A.C.S
Chief Executive Officer

Dr. John Blair has been the CEO of MedAllies for 19 years. Prior to establishing MedAllies as a top health information service provider company, Dr. Blair worked as a general surgeon for 15 years before moving on to become president of Taconic IPA. Dr. Blair is currently serving as the chair of the DirectTrust.org Standards Development Organization Board as well as various other committees and boards. 

He received his medical degree from Rush Medical School in Chicago, completed his surgical training at the University of Texas Medical Center in Dallas and performed his gastrointestinal fellowship at the Middlesex Hospital in London, England.

Dr. Holly Miller, MD, MBA, FHIMSS
Holly Miller, MD, MBA, FHIMSS
Chief Medical Officer

Dr. Miller is an internist who has practiced using serveral EHR systems and has well over two decades of healthcare IT experience. Dr. Miller, who joined MedAllies in 2009, is a physician liaison for all implementation projects and works closely with the team to design change management programs ensuring optimal utilization of health information technology tools within different healthcare environments. Dr. Miller is currently a Co-Chair or member of many Health Information Technology (HIT) Interoperability related committees and workgroups engaged in enhancing healthcare value. These include committees within the following organizations: Sequoia, CareQuality, DaVinci, CMS, DRLS, PACIO, EMDI, 360X, DirectTrust, NCQA, HIMSS, and KLAS. She continues to be a frequent speaker at national conferences.

Dr. Miller earned her MBA at Hautes Etudes Commerciale in Paris and her Doctor of Medicine at Albert Einstein College of Medicine in New York City.

Dianne Koval, MHSA, RHIA, CPEHR
Chief Operating Officer

Dianne Koval has been with MedAllies since its inception in 2001. Previously, Dianne was a director of health information management for several healthcare organizations and professional consulting engagements. Dianne is involved in several national organizations and serves as a career mentor for the University of Pittsburgh health information management program. She is also a registered health information manager (RHIA) and certified professional in electronic health records (CPEHR). 

Dianne received her MS in health services administration from St. Joseph’s College and a BS in health information management from Ithaca College.

Bruce Schreiber
Chief Technology Officer

Bruce Schreiber joined the MedAllies team as chief technology officer in 2019. Most recently, Bruce held a similar position at MaxMD. Prior to that, Bruce was a managing director at Alpha Investment Management and an executive director at CIBC. Bruce was also vice president for Institutional Equity Trading at Lehman Brothers and was the president of BDJ Securities, Inc. Currently, Bruce is Chairman of the Board of DirectTrust. 

Bruce holds undergraduate degrees in Operations Research and Biology from MIT and a Master’s Degree in Electrical Engineering (Computer Science) from Columbia University.

Ethan Yehud, MBA, CISSP, CISA
Ethan Yehud, MBA, CISSP, CISA
Chief Information Officer

Ethan joined MedAllies as our Chief Information Officer in 2019. Previously, Ethan held positions in the management of corporate technology, IT security operations and security programs in highly regulated industries. Ethan has specialized expertise in HIPPA, FISMA, HITRUST, NIST, ISO, PCI-DSS and other regulatory requirements. 

He has his BS in Computer Science from University of Kentucky and his MBA from Indiana University. Ethan is also a Certified Information Systems Security Professional (CISSP) and a Certified Information Systems Auditor (CISA).


Jeannine Castaldi
Chief Financial Officer

Jeannine has been with MedAllies for 11 years. Prior to joining MedAllies, Jeannine held various positions in both accounting and finance at Pepsi Bottling Group and IBM. In addition, Jeannine also worked as a Manager of Technical Accounting. 

Jeannine holds a BS in Accounting and an MBA in Finance, both from Marist College. She also earned her CPA license at KPMG.