He has been affiliated with TCI parent, Telligen and its predecessor (IFMC) for most of the past 30 years; on the Board of Directors, many committees and as interim Medical Director. Dr. Thomas was on the Board of Directors of the American Health Quality Association and president of the association. He is also a long time member of the McFarland Clinic and its treasurer. He is married to the former Sheryl L. Miller, a retired University of Iowa nursing professor. David is the current Board President of Telligen Community Initiative.