PURPOSE: To explore whether the 'hikikomori' syndrome (social withdrawal) 
described in Japan exists in other countries, and if so, how patients with the 
syndrome are diagnosed and treated.
METHODS: Two hikikomori case vignettes were sent to psychiatrists in Australia, 
Bangladesh, India, Iran, Japan, Korea, Taiwan, Thailand and the USA. 
Participants rated the syndrome's prevalence in their country, etiology, 
diagnosis, suicide risk, and treatment.
RESULTS: Out of 247 responses to the questionnaire (123 from Japan and 124 from 
other countries), 239 were enrolled in the analysis. Respondents' felt the 
hikikomori syndrome is seen in all countries examined and especially in urban 
areas. Biopsychosocial, cultural, and environmental factors were all listed as 
probable causes of hikikomori, and differences among countries were not 
significant. Japanese psychiatrists suggested treatment in outpatient wards and 
some did not think that psychiatric treatment is necessary. Psychiatrists in 
other countries opted for more active treatment such as hospitalization.
CONCLUSIONS: Patients with the hikikomori syndrome are perceived as occurring 
across a variety of cultures by psychiatrists in multiple countries. Our results 
provide a rational basis for study of the existence and epidemiology of 
hikikomori in clinical or community populations in international settings.