{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,31]],"date-time":"2026-07-31T20:32:03Z","timestamp":1785529923041,"version":"3.56.0"},"reference-count":102,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2022,8,21]],"date-time":"2022-08-21T00:00:00Z","timestamp":1661040000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>Hikikomori is a form of social withdrawal that is commonly described as having an onset during adolescence, a life stage when other psychiatric problems can also emerge. This study aimed to adapt the 25-item Hikikomori Questionnaire (HQ-25) for the Italian adolescent population, examining its psychometric properties; associations between hikikomori and psychoticism, depression, anxiety, problematic internet use (PIU), psychotic-like experiences (PLEs), to confirm convergent validity of the HQ-25; and the interaction effect between symptoms of hikikomori and PIU in predicting PLEs. Two-hundred and twenty-one adolescents participated in the study. Measures included the HQ-25, the Psychoticism subscale of the Personality Inventory for the Diagnostic and Statistical Manual of Mental Disorders, the Depression and Anxiety subscales of the Brief Symptom Inventory, the Internet Disorder Scale, and the Brief Prodromal Questionnaire. Data showed a satisfactory fit for a three-factor model for the HQ-25 that is consistent with the original study on the HQ-25. Three factors (socialization, isolation, and emotional support) were associated with psychopathology measures. Six participants reported lifetime history of hikikomori. Symptoms of hikikomori and PIU did not interact in predicting PLEs. This is the first study to validate the HQ-25 in a population of adolescents. Findings provide initial evidence of the adequate psychometric properties of the Italian version of the HQ-25 for adolescents.<\/jats:p>","DOI":"10.3390\/ijerph191610408","type":"journal-article","created":{"date-parts":[[2022,8,21]],"date-time":"2022-08-21T22:23:13Z","timestamp":1661120593000},"page":"10408","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Psychometric Properties of the Italian Version of the 25-Item Hikikomori Questionnaire for Adolescents"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1950-4351","authenticated-orcid":false,"given":"Simone","family":"Amendola","sequence":"first","affiliation":[{"name":"Department of Dynamic and Clinical Psychology and Health Studies, Sapienza University of Rome, 00185 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7880-6715","authenticated-orcid":false,"given":"Fabio","family":"Presaghi","sequence":"additional","affiliation":[{"name":"Department of Psychology of Development and Socialization Processes, Sapienza University of Rome, 00185 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alan Robert","family":"Teo","sequence":"additional","affiliation":[{"name":"Center to Improve Veteran Involvement in Care (CIVIC), VA Portland Health Care System, Portland, OR 97239, USA"},{"name":"Department of Psychiatry, Oregon Health & Science University, Portland, OR 97239, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rita","family":"Cerutti","sequence":"additional","affiliation":[{"name":"Department of Dynamic and Clinical Psychology and Health Studies, Sapienza University of Rome, 00185 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,8,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"427","DOI":"10.1111\/pcn.12895","article-title":"Hikikomori: Multidimensional Understanding, Assessment and Future International Perspectives","volume":"73","author":"Kato","year":"2019","journal-title":"Psychiatry Clin. Neurosci."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"116","DOI":"10.1002\/wps.20705","article-title":"Defining Pathological Social Withdrawal: Proposed Diagnostic Criteria for Hikikomori","volume":"19","author":"Kato","year":"2020","journal-title":"World Psychiatry"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"444","DOI":"10.1097\/NMD.0b013e3181e086b1","article-title":"Hikikomori, a Japanese Culture-Bound Syndrome of Social Withdrawal? A Proposal for DSM-5","volume":"198","author":"Teo","year":"2010","journal-title":"J. Nerv. Ment. Dis."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"121","DOI":"10.1111\/j.1440-1819.2011.02292.x","article-title":"Association of Childhood Family Environments with the Risk of Social Withdrawal (\u2018hikikomori\u2019) in the Community Population in Japan","volume":"66","author":"Umeda","year":"2012","journal-title":"Psychiatry Clin. Neurosci."},{"key":"ref_5","first-page":"5017","article-title":"Hikikomori: The Japanese Cabinet Office\u2019s 2016 Survey of Acute Social Withdrawal","volume":"15","author":"Tajan","year":"2017","journal-title":"Asia-Pac. J."},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Coplan, R.J., and Bowker, J.C. (2013). The Intersection of Culture and Solitude: The Hikikomori Phenomenon in Japan. The Handbook of Solitude, Wiley Blackwell.","DOI":"10.1002\/9781118427378"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1131","DOI":"10.1016\/S0140-6736(02)08186-2","article-title":"Public Health Experts Concerned about \u201cHikikomori\u201d","volume":"359","author":"Watts","year":"2002","journal-title":"Lancet"},{"key":"ref_8","first-page":"354","article-title":"Hikikomori (\u3072\u304d\u3053\u3082\u308a): Una culture-bound syndrome nell\u2019era del web 2.0 [Hikikomori (\u3072\u304d\u3053\u3082\u308a): A culture-bound syndrome in the web 2.0 era]","volume":"48","author":"Caredda","year":"2013","journal-title":"Riv. Psichiatr."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"163","DOI":"10.1016\/j.ajp.2017.10.009","article-title":"Hikikomori in Brazil: 29 Years of Voluntary Social Withdrawal","volume":"30","author":"Gondim","year":"2017","journal-title":"Asian J. Psychiatr."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"558","DOI":"10.1177\/0020764009376612","article-title":"\u201cHikikomori\u201d: A New Diagnosis or a Syndrome Associated with a Psychiatric Diagnosis?","volume":"56","author":"Alvaro","year":"2010","journal-title":"Int. J. Soc. Psychiatry"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"562","DOI":"10.1177\/0020764013504560","article-title":"Prolonged Social Withdrawal Disorder: A Hikikomori Case in Spain","volume":"60","author":"Ovejero","year":"2014","journal-title":"Int. J. Soc. Psychiatry"},{"key":"ref_12","first-page":"1932","article-title":"Hikikomori n\u2019est peut-\u00eatre pas ce qu\u2019on voudrait qu\u2019il soit [Hikikomori is perhaps not what we would like it to be]","volume":"8","year":"2012","journal-title":"Rev. Med. Suisse"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"455","DOI":"10.1590\/1516-4446-2020-0804","article-title":"Multimodal Treatment for a Brazilian Case of Hikikomori","volume":"42","author":"Roza","year":"2020","journal-title":"Braz. J. Psychiatry"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"191","DOI":"10.2190\/7WEQ-216D-TVNH-PQJ1","article-title":"Hikikomori, Is It a Culture-Reactive or Culture-Bound Syndrome? Nidotherapy and a Clinical Vignette from Oman","volume":"35","author":"Sakamoto","year":"2005","journal-title":"Int. J. Psychiatry Med."},{"key":"ref_15","first-page":"377","article-title":"Hikikomori Silent Epidemic: A Case Study","volume":"22","author":"Falak","year":"2019","journal-title":"Res. Psychother"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"539","DOI":"10.1177\/0020764019859379","article-title":"No Longer Culture-Bound: Hikikomori Outside of Japan","volume":"65","author":"Bommersbach","year":"2019","journal-title":"Int. J. Soc. Psychiatry"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"318","DOI":"10.1157\/13109125","article-title":"Un caso de hikikomori en Espa\u00f1a [A case report of hikikomori in Spain]","volume":"129","author":"Alda","year":"2007","journal-title":"Med. Clin."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"718","DOI":"10.1157\/13120777","article-title":"Hikikomori o esquizofrenia simple? [Hikikomori or simple schizophrenia?]","volume":"130","author":"Gariup","year":"2008","journal-title":"Med. Clin."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"148","DOI":"10.15557\/PiPK.2015.0023","article-title":"When Social Withdrawal in Adolescence Becomes Extreme: The \u201cHikikomori\u201d Phenomenon in Italy","volume":"15","author":"Ranieri","year":"2015","journal-title":"Psychiatr. Psychol. Klin."},{"key":"ref_20","first-page":"72","article-title":"Hikikomori: Debating a XXI Century Phenomenon from a Clinical Point of View","volume":"6","author":"Ranieri","year":"2018","journal-title":"Scand. J. Child Adolesc. Psychiatry Psychol."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"634941","DOI":"10.3389\/fpsyg.2021.634941","article-title":"Case Report: Burden of Illness in Narcolepsy Type 1: Hikikomori in a Teenage Girl","volume":"12","author":"Filardi","year":"2021","journal-title":"Front. Psychol."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"9068","DOI":"10.4081\/hpr.2020.9068","article-title":"Hikikomori: A Systemic-Relational Analysis","volume":"8","author":"Maglia","year":"2020","journal-title":"Health Psychol. Res."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"217","DOI":"10.1080\/00221325.2019.1633618","article-title":"Severe Social Withdrawal: Cultural Variation in Past Hikikomori Experiences of University Students in Nigeria, Singapore, and the United States","volume":"180","author":"Bowker","year":"2019","journal-title":"J. Genet. Psychol."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"339","DOI":"10.1177\/0020764017704474","article-title":"Characteristics of Socially Withdrawn Youth in France: A Retrospective Study","volume":"63","author":"Chauliac","year":"2017","journal-title":"Int. J. Soc. Psychiatry"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"558","DOI":"10.3389\/fpsyt.2019.00558","article-title":"Similar but Different: Psychological and Psychopathological Features of Primary and Secondary Hikikomori","volume":"10","author":"Frankova","year":"2019","journal-title":"Front. Psychiatry"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1039","DOI":"10.1016\/j.psychres.2018.03.060","article-title":"A 12-Month Study of the Hikikomori Syndrome of Social Withdrawal: Clinical Characterization and Different Subtypes Proposal","volume":"270","author":"Teo","year":"2018","journal-title":"Psychiatry Res."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"182","DOI":"10.1016\/j.psychres.2015.04.033","article-title":"Psychopathology Associated with Social Withdrawal: Idiopathic and Comorbid Presentations","volume":"228","author":"Teo","year":"2015","journal-title":"Psychiatry Res."},{"key":"ref_28","first-page":"106","article-title":"Hikikomori, Problematic Internet Use and Psychopathology: Correlates in Non-Clinical and Clinical Samples of Young Adults in Italy","volume":"27","author":"Amendola","year":"2021","journal-title":"J. Psychopathol."},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Amendola, S., Presaghi, F., Teo, A.R., and Cerutti, R. (2022). Psychometric Properties of the Italian Version of the 25-Item Hikikomori Questionnaire, manuscript submitted for publication.","DOI":"10.3390\/ijerph192013552"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"808","DOI":"10.1007\/s10578-020-01064-8","article-title":"Identifying Social Withdrawal (Hikikomori) Factors in Adolescents: Understanding the Hikikomori Spectrum","volume":"52","author":"Hamasaki","year":"2021","journal-title":"Child Psychiatry Hum. Dev."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"193","DOI":"10.1111\/pcn.12043","article-title":"Home Visitation Program for Detecting, Evaluating and Treating Socially Withdrawn Youth in Korea: Visitation Program for Withdrawn Youth","volume":"67","author":"Lee","year":"2013","journal-title":"Psychiatry Clin. Neurosci."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"247","DOI":"10.1037\/a0032547","article-title":"Longitudinal Associations between Depressive Problems, Academic Performance, and Social Functioning in Adolescent Boys and Girls","volume":"50","author":"Verboom","year":"2014","journal-title":"Dev. Psychol."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"351","DOI":"10.1111\/j.1467-8624.2011.01677.x","article-title":"School Attendance Problems and Youth Psychopathology: Structural Cross-Lagged Regression Models in Three Longitudinal Data Sets: Absenteeism","volume":"83","author":"Wood","year":"2012","journal-title":"Child Dev."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"79","DOI":"10.1177\/0020764011423611","article-title":"General Condition of Hikikomori (Prolonged Social Withdrawal) in Japan: Psychiatric Diagnosis and Outcome in Mental Health Welfare Centres","volume":"59","author":"Kondo","year":"2013","journal-title":"Int. J. Soc. Psychiatry"},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"American Psychiatric Association (2013). Diagnostic and Statistical Manual of Mental Disorders, American Psychiatric Association. [5th ed.].","DOI":"10.1176\/appi.books.9780890425596"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"168","DOI":"10.1016\/j.paid.2016.02.049","article-title":"Pathological Personality Traits and Emotion Regulation Difficulties","volume":"95","author":"Pollock","year":"2016","journal-title":"Personal. Individ. Differ."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"121","DOI":"10.1080\/00223891.2013.823438","article-title":"A Review of Systems for Psychology and Psychiatry: Adaptive Systems, Personality Psychopathology Five (PSY\u20135), and the DSM\u20135","volume":"96","author":"Harkness","year":"2014","journal-title":"J. Personal. Assess."},{"key":"ref_38","first-page":"263","article-title":"Maladaptative Personality Traits in Adolescence: Behavioural, Emotional and Motivational Correlates of the PID-5-BF Scales","volume":"31","author":"Romero","year":"2019","journal-title":"Psicothema"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"229","DOI":"10.3371\/CSRP.4.4.3","article-title":"Trajectories of Social Withdrawal and Cognitive Decline in the Schizophrenia Prodrome","volume":"4","author":"Cullen","year":"2011","journal-title":"Clin. Schizophr. Relat. Psychoses"},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"345","DOI":"10.1016\/j.eurpsy.2013.11.003","article-title":"Difficulty in Making Contact with Others and Social Withdrawal as Early Signs of Psychosis in Adolescents\u2014The Northern Finland Birth Cohort 1986","volume":"29","author":"Koskela","year":"2014","journal-title":"Eur. Psychiatr."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"1061","DOI":"10.1016\/j.jpsychires.2013.03.013","article-title":"Systematic Meta-Analysis of Childhood Social Withdrawal in Schizophrenia, and Comparison with Data from at-Risk Children Aged 9\u201314 Years","volume":"47","author":"Matheson","year":"2013","journal-title":"J. Psychiatr. Res."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"106","DOI":"10.3389\/fpsyt.2014.00106","article-title":"Psychotic-Like Experiences and Their Cognitive Appraisal Under Short-Term Sensory Deprivation","volume":"5","author":"Daniel","year":"2014","journal-title":"Front. Psychiatry"},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"783","DOI":"10.1097\/NMD.0b013e3181b9760b","article-title":"The Psychotomimetic Effects of Short-Term Sensory Deprivation","volume":"197","author":"Mason","year":"2009","journal-title":"J. Nerv. Ment. Dis."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"120","DOI":"10.2174\/1745017901814010154","article-title":"Quick Identification of the Risk of Psychosis: The Italian Version of the Prodromal Questionnaire-Brief","volume":"14","author":"Preti","year":"2018","journal-title":"Clin. Pract. Epidemiol. Ment. Health CP EMH"},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"663","DOI":"10.1001\/archpsyc.58.7.663","article-title":"Prevalence of Psychotic Disorder and Community Level of Psychotic Symptoms: An Urban-Rural Comparison","volume":"58","author":"Hanssen","year":"2001","journal-title":"Arch. Gen. Psychiatry"},{"key":"ref_46","first-page":"41","article-title":"Psychotic-like Experiences and Substance Use in College Students","volume":"32","author":"Inchausti","year":"2019","journal-title":"Adicciones"},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"104","DOI":"10.1016\/j.schres.2012.06.024","article-title":"Trajectories of Change in Self-Reported Psychotic-like Experiences in Childhood and Adolescence","volume":"140","author":"Thapar","year":"2012","journal-title":"Schizophr. Res."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"179","DOI":"10.1017\/S0033291708003814","article-title":"A Systematic Review and Meta-Analysis of the Psychosis Continuum: Evidence for a Psychosis Proneness\u2013Persistence\u2013Impairment Model of Psychotic Disorder","volume":"39","author":"Linscott","year":"2009","journal-title":"Psychol. Med."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"190","DOI":"10.1016\/j.schres.2019.10.033","article-title":"Psychotic-like Experiences during Early Adolescence Predict Symptoms of Depression, Anxiety, and Conduct Problems Three Years Later: A Community-Based Study","volume":"215","author":"Isaksson","year":"2020","journal-title":"Schizophr. Res."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"149","DOI":"10.1016\/j.schres.2017.10.019","article-title":"The Association between Changes in Depression\/Anxiety and Trajectories of Psychotic-like Experiences over a Year in Adolescence","volume":"195","author":"Yamasaki","year":"2018","journal-title":"Schizophr. Res."},{"key":"ref_51","doi-asserted-by":"crossref","unstructured":"Wu, J., Long, X., Liu, F., Qi, A., Chen, Q., Guan, X., Zhang, Q., Yao, Y., Shi, J., and Xie, S. (2021). Screening of the College Students at Clinical High Risk for Psychosis in China: A Multicenter Epidemiological Study. BMC Psychiatry, 21.","DOI":"10.1186\/s12888-021-03229-8"},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"602678","DOI":"10.3389\/fpsyt.2020.602678","article-title":"Psychotic Experiences and Hikikomori in a Nationally Representative Sample of Adult Community Residents in Japan: A Cross-Sectional Study","volume":"11","author":"Yasuma","year":"2021","journal-title":"Front. Psychiatry"},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"1070","DOI":"10.1016\/S0140-6736(11)61475-X","article-title":"Are Japan\u2019s Hikikomori and Depression in Young People Spreading Abroad?","volume":"378","author":"Kato","year":"2011","journal-title":"Lancet"},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"455","DOI":"10.3389\/fpsyt.2019.00455","article-title":"Internet Addiction, Smartphone Addiction, and Hikikomori Trait in Japanese Young Adult: Social Isolation and Social Network","volume":"10","author":"Tateno","year":"2019","journal-title":"Front. Psychiatry"},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"369","DOI":"10.3389\/fpsyt.2019.00369","article-title":"Negative Life Events and Problematic Internet Use as Factors Associated with Psychotic-Like Experiences in Adolescents","volume":"10","author":"Lee","year":"2019","journal-title":"Front. Psychiatry"},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"261","DOI":"10.1111\/j.1751-7893.2012.00390.x","article-title":"Internet Addiction, Reality Substitution and Longitudinal Changes in Psychotic-like Experiences in Young Adults: Internet Addiction and Psychotic-Like","volume":"7","author":"Mittal","year":"2013","journal-title":"Early Interv. Psychiatry"},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"220","DOI":"10.1016\/j.scog.2015.08.002","article-title":"Increased Internet Use and Poorer Ability to Manage Emotions in Youth at High-Risk for Psychosis","volume":"2","author":"Ives","year":"2015","journal-title":"Schizophr. Res. Cogn."},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"S270","DOI":"10.1093\/schbul\/sbaa029.664","article-title":"T104. Psychotic-like Experiences and Problematic Gaming Behavior in Online Game Forums","volume":"46","author":"Goreis","year":"2020","journal-title":"Schizophr. Bull."},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"8","DOI":"10.1016\/j.addbeh.2016.05.001","article-title":"Associations between Problematic Gaming and Psychiatric Symptoms among Adolescents in Two Samples","volume":"61","author":"Vadlin","year":"2016","journal-title":"Addict. Behav."},{"key":"ref_60","doi-asserted-by":"crossref","first-page":"6","DOI":"10.3389\/fpsyt.2016.00006","article-title":"Internet Addiction, Hikikomori Syndrome, and the Prodromal Phase of Psychosis","volume":"7","author":"Stip","year":"2016","journal-title":"Front. Psychiatry"},{"key":"ref_61","doi-asserted-by":"crossref","first-page":"89","DOI":"10.4103\/aip.aip_84_20","article-title":"Psychosis Unmasked by Gaming: A Case Series","volume":"5","author":"Angane","year":"2021","journal-title":"Ann. Indian Psychiatry"},{"key":"ref_62","doi-asserted-by":"crossref","first-page":"144","DOI":"10.1159\/000085845","article-title":"\u2018Internet Delusions\u2019: A Case Series and Theoretical Integration","volume":"38","author":"Bell","year":"2005","journal-title":"Psychopathology"},{"key":"ref_63","doi-asserted-by":"crossref","first-page":"623","DOI":"10.1097\/NMD.0000000000000173","article-title":"Twitter Psychosis: A Rare Variation or a Distinct Syndrome?","volume":"202","author":"Kalbitzer","year":"2014","journal-title":"J. Nerv. Ment. Dis."},{"key":"ref_64","first-page":"47","article-title":"\u201cInternet Delusions\u201d: The Impact of Technological Developments on the Content of Psychiatric Symptoms","volume":"43","author":"Lerner","year":"2006","journal-title":"Isr. J. Psychiatry Relat. Sci."},{"key":"ref_65","doi-asserted-by":"crossref","first-page":"163","DOI":"10.1111\/j.1440-1819.2011.02306.x","article-title":"Emergence of Psychotic Symptoms during Internet Withdrawal: Letters to the Editor","volume":"66","author":"Mendhekar","year":"2012","journal-title":"Psychiatry Clin. Neurosci."},{"key":"ref_66","first-page":"207","article-title":"Internet-Related Psychosis\u2014A Sign of the Times?","volume":"48","author":"Nitzan","year":"2011","journal-title":"Isr. J. Psychiatry"},{"key":"ref_67","doi-asserted-by":"crossref","first-page":"207","DOI":"10.4306\/pi.2014.11.2.207","article-title":"A Case of Withdrawal Psychosis from Internet Addiction Disorder","volume":"11","author":"Paik","year":"2014","journal-title":"Psychiatry Investig."},{"key":"ref_68","first-page":"143","article-title":"Paranoid Schizophrenia with Delusions Regarding the Internet","volume":"22","author":"Tan","year":"1997","journal-title":"J. Psychiatry Neurosci."},{"key":"ref_69","doi-asserted-by":"crossref","first-page":"384","DOI":"10.1111\/pcn.12243","article-title":"Adolescent\u2019s Psychotic-like Symptoms Associated with Internet Addiction","volume":"69","author":"Tzang","year":"2015","journal-title":"Psychiatry Clin. Neurosci."},{"key":"ref_70","doi-asserted-by":"crossref","first-page":"1066","DOI":"10.1093\/schbul\/sbm079","article-title":"A Social Deafferentation Hypothesis for Induction of Active Schizophrenia","volume":"33","author":"Hoffman","year":"2007","journal-title":"Schizophr. Bull."},{"key":"ref_71","doi-asserted-by":"crossref","first-page":"471","DOI":"10.1080\/09540261.2019.1636005","article-title":"Loneliness and the Psychosis Continuum: A Meta-Analysis on Positive Psychotic Experiences and a Meta-Analysis on Negative Psychotic Experiences","volume":"31","author":"Chau","year":"2019","journal-title":"Int. Rev. Psychiatry"},{"key":"ref_72","doi-asserted-by":"crossref","first-page":"780","DOI":"10.1111\/pcn.12691","article-title":"Development and Validation of the 25-item Hikikomori Questionnaire (HQ-25)","volume":"72","author":"Teo","year":"2018","journal-title":"Psychiatry Clin. Neurosci."},{"key":"ref_73","doi-asserted-by":"crossref","first-page":"149","DOI":"10.1186\/s13052-019-0725-8","article-title":"Media Use during Adolescence: The Recommendations of the Italian Pediatric Society","volume":"45","author":"Bozzola","year":"2019","journal-title":"Ital. J. Pediatr."},{"key":"ref_74","first-page":"129","article-title":"Hikikomori: La sofferenza silenziosa dei giovani","volume":"56","author":"Cerutti","year":"2021","journal-title":"Riv. Psichiatr."},{"key":"ref_75","doi-asserted-by":"crossref","first-page":"286","DOI":"10.1016\/j.jpeds.2020.06.089","article-title":"The Hikikomori Phenomenon of Social Withdrawal: An Emerging Condition Involving Youth\u2019s Mental Health and Social Participation","volume":"225","author":"Ferrara","year":"2020","journal-title":"J. Pediatr."},{"key":"ref_76","doi-asserted-by":"crossref","first-page":"187","DOI":"10.1080\/13651501.2020.1820524","article-title":"Hikikomori: Psychopathology and Differential Diagnosis of a Condition with Epidemic Diffusion","volume":"25","author":"Martinotti","year":"2021","journal-title":"Int. J. Psychiatry Clin. Pract."},{"key":"ref_77","doi-asserted-by":"crossref","unstructured":"Masi, G., Berloffa, S., Milone, A., and Brovedani, P. (2021). Social Withdrawal and Gender Differences: Clinical Phenotypes and Biological Bases. J. Neurosci. Res., jnr.24802.","DOI":"10.1002\/jnr.24802"},{"key":"ref_78","doi-asserted-by":"crossref","first-page":"e025213","DOI":"10.1136\/bmjopen-2018-025213","article-title":"The \u2018Hikikomori\u2019 Syndrome: Worldwide Prevalence and Co-Occurring Major Psychiatric Disorders: A Systematic Review and Meta-Analysis Protocol","volume":"9","author":"Pozza","year":"2019","journal-title":"BMJ Open"},{"key":"ref_79","doi-asserted-by":"crossref","first-page":"615","DOI":"10.1177\/1073191115621793","article-title":"The Personality Inventory for DSM-5 Brief Form: Evidence for Reliability and Construct Validity in a Sample of Community-Dwelling Italian Adolescents","volume":"24","author":"Fossati","year":"2017","journal-title":"Assessment"},{"key":"ref_80","doi-asserted-by":"crossref","first-page":"680","DOI":"10.1007\/s11469-017-9823-2","article-title":"Assessment of the Italian Version of the Internet Disorder Scale (IDS-15)","volume":"16","author":"Monacis","year":"2018","journal-title":"Int. J. Ment. Health Addict."},{"key":"ref_81","doi-asserted-by":"crossref","first-page":"261","DOI":"10.1016\/j.addbeh.2015.09.003","article-title":"The Development and Psychometric Evaluation of the Internet Disorder Scale (IDS-15)","volume":"64","author":"Pontes","year":"2017","journal-title":"Addict. Behav."},{"key":"ref_82","unstructured":"Derogatis, L.R. (1975). Brief Symptom Inventory, Clinical Psychometric Research."},{"key":"ref_83","doi-asserted-by":"crossref","first-page":"145","DOI":"10.2147\/PRBM.S173282","article-title":"Psychometric Properties of the Brief Symptom Inventory in Nomophobic Subjects: Insights from Preliminary Confirmatory Factor, Exploratory Factor, and Clustering Analyses in a Sample of Healthy Italian Volunteers","volume":"12","author":"Adawi","year":"2019","journal-title":"Psychol. Res. Behav. Manag."},{"key":"ref_84","doi-asserted-by":"crossref","first-page":"42","DOI":"10.1016\/j.schres.2011.03.029","article-title":"Psychosis Risk Screening with the Prodromal Questionnaire\u2014Brief Version (PQ-B)","volume":"129","author":"Loewy","year":"2011","journal-title":"Schizophr. Res."},{"key":"ref_85","doi-asserted-by":"crossref","first-page":"234","DOI":"10.1159\/000490708","article-title":"The Italian Version of the Brief 21-Item Prodromal Questionnaire: Field Test, Psychometric Properties and Age-Sensitive Cut-Offs","volume":"51","author":"Pelizza","year":"2018","journal-title":"Psychopathology"},{"key":"ref_86","first-page":"204","article-title":"Reliability of the Italian Version of the Brief (21-Item) Prodromal Questionnaire (IPQ-B) for Psychosis Risk Screening in a Young Help-Seeking Population","volume":"24","author":"Scazza","year":"2018","journal-title":"J. Psychopathol."},{"key":"ref_87","doi-asserted-by":"crossref","first-page":"3","DOI":"10.1111\/eip.12446","article-title":"Psychosis Risk Screening in Different Populations Using the Prodromal Questionnaire: A Systematic Review","volume":"12","author":"Savill","year":"2018","journal-title":"Early Interv. Psychiatry"},{"key":"ref_88","doi-asserted-by":"crossref","first-page":"102415","DOI":"10.1016\/j.janxdis.2021.102415","article-title":"The Latent and Item Structure of COVID-19 Fear: A Comparison of Four COVID-19 Fear Questionnaires Using SEM and Network Analyses","volume":"81","author":"Mertens","year":"2021","journal-title":"J. Anxiety Disord."},{"key":"ref_89","unstructured":"McDonald, R.P. (1999). Test Theory: A Unified Treatment, Lawrence Erlbaum."},{"key":"ref_90","unstructured":"R Core Team, R. A Language and Environment for Statistical Computing, R Foundation for Statistical Computing. Available online: https:\/\/www.R-project.org\/."},{"key":"ref_91","doi-asserted-by":"crossref","first-page":"1","DOI":"10.18637\/jss.v048.i02","article-title":"Lavaan: An R Package for Structural Equation Modeling","volume":"48","author":"Rosseel","year":"2012","journal-title":"J. Stat. Soft."},{"key":"ref_92","unstructured":"Revelle, W.R. (2021, November 28). Psych: Procedures for Personality and Psychological Research. Available online: https:\/\/CRAN.R-project.org\/package=psych."},{"key":"ref_93","unstructured":"Zhang, Z., and Yuan, K.H. (2021, November 28). Coefficientalpha: Robust Coefficient Alpha and Omega with Missing and Non-Normal Data. Available online: https:\/\/CRAN.R-project.org\/package=coefficientalpha."},{"key":"ref_94","doi-asserted-by":"crossref","first-page":"304","DOI":"10.1016\/j.psychres.2015.09.010","article-title":"\u201cNo Man Is an Island\u201d. Testing the Specific Role of Social Isolation in Formal Thought Disorder","volume":"230","author":"Spray","year":"2015","journal-title":"Psychiatry Res."},{"key":"ref_95","doi-asserted-by":"crossref","first-page":"119","DOI":"10.1007\/s00406-021-01278-4","article-title":"Social Isolation and Psychosis: An Investigation of Social Interactions and Paranoia in Daily Life","volume":"272","author":"Fett","year":"2022","journal-title":"Eur. Arch. Psychiatry Clin. Neurosci."},{"key":"ref_96","doi-asserted-by":"crossref","first-page":"923","DOI":"10.1017\/S0033291710001546","article-title":"Concomitants of Paranoia in the General Population","volume":"41","author":"Freeman","year":"2011","journal-title":"Psychol. Med."},{"key":"ref_97","unstructured":"Ufficio Scolastico Regionale per l\u2019Emilia-Romagna\u2014Ministero dell\u2019Istruzione Adolescenti \u201cEremiti Sociali\u201d (2020, March 11). Rilevazione Nelle Scuole Dell\u2019Emilia-Romagna Degli Alunni Che Non Frequentano, \u201cRitirati\u201d in Casa, per Motivi Psicologici. Available online: https:\/\/bit.ly\/3rC7KtJ."},{"key":"ref_98","doi-asserted-by":"crossref","first-page":"274","DOI":"10.1007\/s11199-014-0357-9","article-title":"Gender Differences in Child and Adolescent Social Withdrawal: A Commentary","volume":"70","author":"Rubin","year":"2014","journal-title":"Sex Roles"},{"key":"ref_99","doi-asserted-by":"crossref","unstructured":"Amendola, S., Hengartner, M.P., Spensieri, V., Grillo, L., and Cerutti, R. (2021). Patterns of Internalizing Symptoms and Disability Functioning in Children and Adolescents. Eur. Child Adolesc. Psychiatry.","DOI":"10.1007\/s00787-021-01789-4"},{"key":"ref_100","doi-asserted-by":"crossref","first-page":"77","DOI":"10.1016\/j.jadohealth.2017.01.016","article-title":"Sex Differences in Quality of Life Impairment Associated With Body Dissatisfaction in Adolescents","volume":"61","author":"Griffiths","year":"2017","journal-title":"J. Adolesc. Health"},{"key":"ref_101","doi-asserted-by":"crossref","unstructured":"Spensieri, V., Cerutti, R., Presaghi, F., Amendola, S., and Crozier, W.R. (2019). Italian Validation of the Children\u2019s Shyness Questionnaire: Exploring Associations between Shyness and Psychosocial Functioning. PLoS ONE, 14.","DOI":"10.1037\/t73229-000"},{"key":"ref_102","doi-asserted-by":"crossref","first-page":"149","DOI":"10.1007\/s10826-010-9435-y","article-title":"Behavioral Inhibition and Attentional Control in Adolescents: Robust Relationships with Anxiety and Depression","volume":"20","author":"Sportel","year":"2011","journal-title":"J. Child Fam. Stud."}],"container-title":["International Journal of Environmental Research and Public Health"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1660-4601\/19\/16\/10408\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T00:13:07Z","timestamp":1760141587000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1660-4601\/19\/16\/10408"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,8,21]]},"references-count":102,"journal-issue":{"issue":"16","published-online":{"date-parts":[[2022,8]]}},"alternative-id":["ijerph191610408"],"URL":"https:\/\/doi.org\/10.3390\/ijerph191610408","relation":{},"ISSN":["1660-4601"],"issn-type":[{"value":"1660-4601","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,8,21]]}}}