JOURNAL OF MEDICAL INTERNET RESEARCH Pereira-Sanchez et al Original Paper Exploring the Extent of the Hikikomori Phenomenon on Twitter: Mixed Methods Study of Western Language Tweets Victor Pereira-Sanchez1*, MD; Miguel Angel Alvarez-Mon1*, MD; Angel Asunsolo del Barco2,3,4, MD, PhD; Melchor Alvarez-Mon3,5,6, MD, PhD; Alan Teo7,8,9, MD, MS 1Department of Psychiatry, Clinica Universidad de Navarra, Pamplona, Spain 2Department of Surgery, Medical and Social Sciences, University of Alcala, Madrid, Spain 3Instituto Ramon y Cajal de Investigaciones Sanitarias, Madrid, Spain 4Department of Epidemiology & Biostatistics, Graduate School of Public Health and Health Policy, University of New York, New York, NY, United States 5Department of Medicine and Medical Specialities, University of Alcala, Madrid, Spain 6Service of Internal Medicine, Autoimmune Diseases and Rheumatology, Hospital Universitario Principe de Asturias, Madrid, Spain 7Department of Psychiatry, Oregon Health & Science University, Portland, OR, United States 8School of Public Health, Oregon Health & Science University and Portland State University, Portland, OR, United States 9Center to Improve Veteran Involvement in Care, VA Portland Health Care System, Department of Veterans Affairs (VA), Portland, OR, United States *these authors contributed equally Corresponding Author: Miguel Angel Alvarez-Mon, MD Department of Psychiatry Clinica Universidad de Navarra Avda Pio XII, 36 Pamplona, 31008 Spain Phone: 34 948255400 Email:
[email protected] Abstract Background: Hikikomori is a severe form of social withdrawal, originally described in Japan but recently reported in other countries. Debate exists as to what extent hikikomori is viewed as a problem outside of the Japanese context. Objective: We aimed to explore perceptions about hikikomori outside Japan by analyzing Western language content from the popular social media platform, Twitter.