Dr Davies trained in Birmingham, UK from 1985 to 1990 and subsequently worked in the West Midlands and Oxford hospitals before embarking on a career in respiratory medicine. He completed his specialist training in 1999 after working at High Wycombe, Banbury, and the Churchill and John Radcliffe Hospitals, Oxford. During this time he completed a doctorate based on work around pneumonia and pleural disease and produced several studies about obstructive sleep apnoea and cardiovascular risks.
He commenced as a consultant physician in Reading in January 2000 and is the Clinical Lead for the Department of Respiratory Medicine in the Royal Berkshire NHS Foundation Trust. He has been Clinical Director of Acute Medicine between 2004 and 2008, the Training Programme Director for Respiratory Medicine for Oxford Deanery between 2006 and 2011 and a member of the Specialty Advisory Committee for Respiratory Medicine at the Joint Royal Colleges Postgraduate Training Board between 2007 and 2011(JRCPTB). He has also been the Regional Specialty Advisor for Respiratory Medicine between 2006 and 2014, the Director of Core Medical Training for the Oxford Deanery/Health Education Thames Valley between 2011 and 2015 and a member of the School of Medicine Executive Board.
In addition he has been lead author of the British Thoracic Society Pleural Guidelines on pleural infection published in 2003 and 2010, and has published over 40 papers in peer reviewed journals and textbooks. He is currently a member of the British Thoracic Society Pulmonary Embolism Guidelines Group.
His main interests other than general respiratory medicine are pleural disease, pulmonary emboli and sleep related breathing disorders including sleep apnoea. He is actively involved with all other aspects of respiratory medicine, especially airway disease and suspected lung cancer. He has written over 500 medicolegal reports predominantly in the field of asbestos related lung diseases, but also covering many other aspects of thoracic medicine and some negligence cases.