He obtained the master's degree of Research in 2011. His fields of interests are: digestive and bariatric surgery and surgical oncology. His research focuses on the effects of Vagus Nerve Stimulation on Weight Loss and Associated Disorders. He is creator of application ” Scan abdo” for iphone and android. Dr Kassir is director of collection : qroc en poche (28 medical books, publisher : vernazobres-grego). He is author of 8 books of medicine published in Europe. He has authored more than 30 peer-reviewed articles with a focus on digestive and bariatric surgery. He has served as reviewer of over 10 international journals such as International Journal of Surgery case reports, World Journal of Emergency Surgery, British Médical Journal BMJ case reports, World Journal of Surgery.