Temperature-variable apparatus for measuring Barnett field.

We have developed experimental equipment for observing the Barnett effect, in which mechanical rotation magnetizes an object, at low temperatures. A sample in a rotor is rotated bidirectionally using a temperature-controlled high-pressure gas. The stray field generated from the sample due to the Barnett effect was detected using a fluxgate magnetic sensor with a sensitivity on the order of several picoteslas, even at low temperatures. By replacing the rotor with a solenoid coil, the magnetic susceptibility of the sample was estimated from the stray field to be of the same order of magnitude as that due to the Barnett effect. The Barnett field was estimated using the dipole model. To assess the performance of the setup at low temperatures, measurements were performed on commercial magnetite (Fe3O4) nanogranules. We confirmed the accordance of the g' factor between the experimental results using the present setup and those of our previous study performed at room temperature.

[Developing scales to evaluate community practices among municipal public health nurses: content, perceptions of public health nurses, and organizational environment].

Objectives　This study aimed to develop scales for evaluating the level of implementation of community practices and explore the perception of public health nurses in municipalities regarding their community practices.Methods　Draft scales were developed based on a literature review and interviews with municipal public health nurses. Subsequently, a questionnaire survey was conducted with municipal public health nurses across Japan in response to these draft scales. Respondents were recruited based on the municipality population size. Questionnaires were distributed to 2,074 individuals from 52 municipalities ensuring representation from diverse municipalities. Exploratory factor analysis was performed to determine the number of factors, while confirmatory factor analysis was performed to determine the factor structure. The reliability of the scales was assessed by calculating Cronbach's alpha coefficients, and their validity was tested by examining correlations with existing scales, namely the Moral Competence Scale for Public Health Nurses and the Professional Identity Scale for Public Health Nurses, and years of experience as a public health nurse.Results　A total of 721 (34.8%) valid respondents were included in the analysis. Three scales, methods of community practices (three factors, nine items), perceptions of public health nurses toward community residents through community practices (three factors, 10 items), and organizational environment supporting community practices (two factors, 11 items) were developed as indicators of the implementation of public health nurses' community practices. Cronbach's alpha coefficients for the three scales were 0.896, 0.913, and 0.868, respectively. As hypothesized, each subfactor exhibited a positive correlation with the existing scales. However, certain subfactors did not demonstrate any correlation with years of experience.Conclusion　The three scales developed in this study were individually examined for reliability and validity. These scales can be used independently or in combination, allowing public health nurses to select the most suitable scale(s) based on their objective.　A notable contribution of this study is the establishment of concrete indicators for evaluating community practices, addressing the previously vague nature of this evaluation. By incorporating the scale items into daily health practices, we anticipate that these indicators can be employed to evaluate community practices at the organizational and individual levels.

Effects of disaster-related traumatic events on worry about radiation and COVID-19: A decade after the Fukushima nuclear power plant accident.

Community residents exposed to nuclear power plant (NPP) accidents have long-term worry about the effects of radiation. After the 2011 Fukushima NPP accident, those who experienced traumatic events during the Great East Japan Earthquake (GEJE) tended to have greater worry about radiation. Along with the prolonged worry about radiation, there may also be cognitive changes caused by the traumatic events. We hypothesized that if there were cognitive changes underlying the prolonged worry about radiation, those who experienced the traumatic events would tend to have greater worry about other issues unrelated to radiation. We examined the effects of the traumatic events during the GEJE on community residents' worry about radiation and COVID-19 a decade after the Fukushima NPP accident. Using the data of a longitudinal questionnaire survey following a random sample of 4900 community residents outside the evacuation zone in Fukushima, this study analyzed 774 responses (15.8%). The traumatic events consisted of (1) injury, (2) injury or death of a family member, and (3) the loss of a house or other property. We developed a mediation model drawing paths from the traumatic events to worry about radiation and COVID-19, including posttraumatic stress symptoms (PTSS) as a mediator, using structural equation modeling. The traumatic events directly affected worry about radiation. Although it did not directly affect worry about COVID-19, it did so indirectly through worry about radiation and PTSS. Traumatic events can increase trauma-related worry independently of PTSS and increase trauma-unrelated worry indirectly through trauma-related worry and PTSS.

Nonlinear Magnon Polaritons.

We experimentally and theoretically demonstrate that nonlinear spin-wave interactions suppress the hybrid magnon-photon quasiparticle or "magnon polariton" in microwave spectra of a yttrium iron garnet film detected by an on-chip split-ring resonator. We observe a strong coupling between the Kittel and microwave cavity modes in terms of an avoided crossing as a function of magnetic fields at low microwave input powers, but a complete closing of the gap at high powers. The experimental results are well explained by a theoretical model including the three-magnon decay of the Kittel magnon into spin waves. The gap closure originates from the saturation of the ferromagnetic resonance above the Suhl instability threshold by a coherent backreaction from the spin waves.

Worry about Radiation and Its Risk Factors Five to Ten Years after the Fukushima Nuclear Power Plant Disaster.

Worry about radiation persists long after nuclear power plant accidents. Young age, low socioeconomic status, being married, and disaster-related experiences are known to be associated with greater worry about radiation. This study explored the duration of the effects of these risk factors on worry about radiation after the 2011 Fukushima nuclear power plant accident, using the longitudinal data of randomly sampled non-evacuee community residents who were followed five to ten years after the accident. Questionnaire surveys were conducted five times with 1825 respondents (37.2% of the 4900 initial targets). We examined the interaction of time and risk factors of worry about radiation using a mixed model. Fear or anxiety immediately after the accident had effects on worry about radiation that continued even after 10 years, though it slightly attenuated with time. Family problems stemming from the disaster retained their effects. While direct damage and evacuation experience were significantly associated with worry about radiation in the early phase, their effects diminished and became non-significant during the study period. Being under the age of 65, having low educational attainment, and being married were significantly associated with worry about radiation, although the association with age weakened over time. Individuals who experience intense fear or anxiety post-nuclear power plant accidents or disaster-related family problems may need continuous monitoring for their worry about radiation even 10 years after such accidents.

Difficulties in providing genetic consultations by public health nurses in Japan.

OBJECTIVE: The objectives of this study were to identify the topics that Japanese public health nurses (PHNs) find difficult during genetic consultations and to identify the relationships between these difficulties and PHNs' genetic education. METHODS: We conducted a mail survey delivered to PHNs employed by local Japanese governmental agencies in the Tokyo metropolitan area, between July and October 2015. The self-administered questionnaire queried the (1) experience with genetic consultation, (2) perceived difficulties in genetic consultation, (3) genetics education background, and (4) demographics. The association between the perceived difficulties in genetic consultations and the genetics education opportunities was examined using logistic regression. RESULTS: Of the 907 mailed surveys, 536 PHNs responded (59.1% response rate). Most of the respondents (89.7%) had previously conducted genetic consultations. The majority of respondents (72.7%) had partaken in consultations regarding a possible hereditary disorder in the client or their families, and of those, 76.6% perceived difficulties during the genetic consultation. Respondents who had previously studied decision-making support for genetic testing were significantly less likely to perceive difficulties in genetic consultations on prenatal diagnosis (OR = 0.04, 95% CI [0.00-0.73]). CONCLUSIONS: Our results suggest that PHNs receive training in genetic consultation, which can be integrated into everyday practice.

[Changes in long-term care certification rate and related factors in municipalities affected by the heavy rain disaster in July 2018].

Objectives　The purpose of this study was to determine the change in the certification rate for long-term care (LTC) in the municipalities affected by the heavy rain disaster in July 2018, and to clarify the relationships between the change in the LTC certification rate and the damage situation and regional characteristics.Methods　The subjects were 108 municipalities to which the Disaster Relief Act was applied. Interrupted time series analyses were conducted of the monthly LTC certification rate for a total of 37 months from July 2016 to July 2019, and the changes in the LTC, mild LTC (requiring support 1 and 2), moderate LTC (requiring long-term care 1 to 3), and severe LTC (requiring long-term care 4 and 5) certification rates after the disaster were determined. Multinomial logistic regression analyses were performed to clarify the relationship between trends of changes in the LTC certification rate after the disaster, the damage situation (number of damaged houses, number of dead and missing), and the regional characteristics (population rate of people aged 65 and over, population density, taxable income, population per public health nurse, capacity of long-term care insurance facilities, number of hospital beds, number of clinics, specific health examination implementation rate, and specific health guidance implementation rate).Results　The LTC and mild LTC certification rates showed significant increases in the month of the disaster and changes in trends after the disaster. The change in the post-disaster trend of the moderate LTC certification rate was significantly lower. The severe LTC certification rate showed a significant increase only in the month of the disaster; however, there was no significant change seen in the post-disaster trend. The downward change in the trend of the moderate LTC certification rate was negatively related to the population rate of people aged 65 and over, and positively related to the number of clinics. No significant associations of the LTC, mild LTC, and severe LTC certification rates with any of the variables related to the disaster situation and regional characteristics were found.Conclusion　The results of this study suggest that the demand for long-term care insurance services may increase as a result of disasters experienced by elderly requiring mild LTC certification who have a relatively high degree of independence.

Early menarche and adult major depressive disorder among Japanese women: The role of childhood traumatic experience and socioeconomic conditions in young adulthood.

Aim: The aim of this study is to examine the long-term impact of early menarche with adult depression, and to assess whether this association was explained by childhood traumatic experience and socioeconomic condition in early adulthood. Methods: The data were derived from World Mental Health Survey Japan Second, a cross-sectional survey conducted among Japanese community residents between 2013 and 2015. We used the data of female respondents aged 20-75 years (N = 1171). Hazard ratio (HR) of the onset of major depression up to 40 years was calculated for an early-menarche group and a non-early-menarche group, respectively. Kaplan-Meier curve and log-rank statistics were used to examine the difference in failure. Cox proportional hazard models were administered for the association of major depression with early-menarche and early-life psychosocial factors. Results: Risk for major depressive disorders were three to four times higher in an early-menarche group, and the differences in survival functions were significant (p < 0.001). HR of early menarche was 2.79 (95% CI = 1.29-6.02), and was slightly changed when childhood traumatic experience and socioeconomic conditions in young adulthood were added in the model (HR = 2.88, 95% CI = 1.30-6.38; HR = 3.19, 95% CI = 1.41-7.21). Conclusion: Early menarche was significantly associated with increased risk for depression by the age of 40 years. Childhood trauma and socioeconomic hardship in early adulthood did not account for the association. Both physical and psychosocial risk factors in early life need to be addressed for preventing women's depression.

Association between Urban Upbringing and Compulsive Internet Use in Japan: A Cross-Sectional, Multilevel Study with Retrospective Recall.

The purpose of this study was to show the association between urban upbringing and compulsive internet use (CIU). The interview data of the sample (N = 2431) was obtained from the World Mental Health Japan Second Survey and a multilevel model was used to investigate the association. Multiple imputation was also conducted in this study. Growing up in a large city was significantly associated with higher Compulsive Internet Use Scale (CIUS) scores (γ = 1.65, Standard Error (SE) = 0.45) and Mild CIU + Severe CIU (Exp(γ) = 1.44; 95% Confidence Interval (CI) (1.04-2.00)) compared to growing up in a small municipality after adjusting for both sociodemographic characteristics and psychopathology. This study showed a possible association between urban upbringing and CIU. Future studies with longitudinal design are needed to better understand this association.

Burden of caregivers who care for oldest-old parents with disability: A cross-sectional study.

OBJECTIVE: To describe the characteristics of oldest-old Chinese with disability and their adult-child caregivers, and the extent to which these characteristics were associated with caregiver burden. METHODS: The study was based on 168 pairs of disabled oldest-old adults and their adult-child caregivers, derived from the Chinese Longitudinal Healthy Longevity Survey. Descriptive analyses of care recipients' and caregivers' characteristics were conducted respectively, in reference to caregiver burden. Statistically significant characteristics identified in these bivariate analyses were then jointly evaluated in multiple linear regression models with caregiver burden as the outcome. RESULTS: Care recipients positive emotion status [(ß = -0.227 (-0.412, -0.042)], multiple chronic disease [(ß = 0.513 (0.081, 0.945)], and caregivers spent more caregiving time [(ß = 0.225 (0.061, 0.389)] were main factors associated with caregiver burden. CONCLUSION: Adult-children caregivers perceived heavier burden if care recipients had low positive emotions, had multiple chronic diseases, and caregivers spent more time caregiving.

Stress, Anxiety, and Depression for Chinese Residents in Japan during the COVID-19 Pandemic.

The coronavirus disease 2019 (COVID-19) has profoundly affected the psychological well-being of foreign residents. This study examines stress, anxiety, and depression levels in Chinese residents in Japan during the COVID-19 pandemic. It identifies risk factors and the roles of disaster preparedness and social support. An online survey among Chinese residents in Japan was conducted from 22 June to 14 July 2020. The Depression, Anxiety and Stress Scale, Disaster Preparedness for Resilience Checklist, and Social Support Rate Scale were used to measure psychological symptoms. Multivariable linear regressions identified the risk factors and positive effects of disaster preparedness and social support. Of the total 497 participants, 45.3%, 66.6%, and 54.3% reported severe stress, anxiety, and depressive symptoms, respectively. People with a lower level of education, a higher level of economic influence, the presence of COVID-19 symptoms, and confirmed or suspected family or friends in China were associated with higher levels of stress, anxiety, and depression. This study, to the best of our knowledge, is the first survey to reveal the protective role of disaster preparedness in reducing psychological symptoms during the pandemic. It offers unique data for further research on how to promote the mental health of vulnerable populations including foreign residents.

[Gaining consensus on key terms in community health activities: A national survey using the Delphi method].

Objectives　The purpose of this study was to define the terminology used in community health activities by systematically establishing agreement among public health nurses and related professionals, to aid them in effectively cooperating with other professionals.Methods　We extracted the major terms described in "Guidelines for Public Health Nurses' Activities in the Region," which was issued by the Director of Health Bureau, Ministry of Health, Labor and Welfare; and conducted 2 iterations on the proposed definition of the terms using the Delphi method. The survey targeted 800 stakeholders from the following 4 professions: public health nurses in managerial positions in local governments, clerical staff in local governments, public health nursing professors at educational institutions, and social welfare council staff. Respondents indicated their degree of agreement with the definition of the terms using a 4-point Likert scale. We tallied the answers indicating "I agree" or "Mostly agree." A 70% term agreement was considered "conformed." A free text box for each proposed definition was also available so that respondents could share their opinions and offer alternatives.Results　The first survey received 231 responses. The conformity of their definitions ranged from 83.9%-96.9% (mean=91.5%). Although all definitions exceeded the consensus level, we examined their adequacy with reference to the definitions and opinions from the free text. Various opinions were obtained from those engaged in each occupation. The second round included 117 consenting stakeholders from the first survey, yielding 90 responses. Their degree of conformity ranged from 86.7%-98.9% (mean=94.6%). Therefore, we determined the definitions had reached a robust agreement. We revised the definitions of some terms with reference to the opinions from the free texts and finalized the definitions. Finally, we defined 23 terms-such as region, community diagnosis, and policy.Conclusion　All terms had a conformity of more than 85%, thus bringing into alignment those community health terms that had varying interpretations among related occupations earlier. By including the opinions of those from the related occupations who collaborate with public health nurses, the definitions of these terms could be established and shared. These definitions can be used in public health nursing practice, education, service, and research-among those in involved these related occupations.

Association between Work Environments and Stigma towards People with Schizophrenia among Mental Health Professionals in Japan.

This study aimed to examine the association between control over practice in work environments and stigma toward people with schizophrenia among mental health professionals. We conducted secondary analyses on data from a self-administered questionnaire survey. The sample in the initial study included mental health professionals from two psychiatric hospitals, 56 psychiatric clinics, and community service agencies in Japan. The Ethics Committee of the University of Tokyo, approved this study. Data from 279 participants were used for secondary analyses (valid response rate = 58.7%). The hierarchical multiple regression analysis was used to determine the association between control over practice and stigma. We performed subgroup analyses among nurses (n = 121) and psychiatric social workers (n = 92). Control over practice was negatively associated with stigma among mental health professionals (ß = -0.162, p < 0.01). The subgroup analyses among nurses indicated that control over practice, educational history and recovery knowledge were associated with stigma. However, these variables were not associated with stigma among psychiatric social workers. Control over practice might help to reduce stigma among mental health professionals. Factors related to stigma might differ by occupation. Therefore, further comprehensive studies among various professionals would further our understanding of these factors.

Distrust in government and its relationship with mental health after the Fukushima nuclear power plant accident.

BACKGROUND: Distrust in authorities has negative effects on mental health. AIMS: In this study, we aimed to explore whether the impact of distrust in government on mental health became stronger in the area heavily affected by the 2011 Fukushima nuclear power plant accident. METHODS: We examined the effects of distrust in the national government on depressive symptoms three years after the accident among community residents in Fukushima prefecture using those in the Kanto area (the area surrounding Tokyo) as a control. A questionnaire survey was administered to a random sample of 1000 residents in Fukushima prefecture and 1650 residents in the Kanto area. Distrust in the national government was assessed using a four-point single-item scale. Depressive symptoms were measured using the Patient Health Questionnaire-9. The associations of residential area (i.e. living in Fukushima prefecture or in the Kanto area) and distrust in the national government with depressive symptoms were examined, controlling for socio-demographic characteristics and disaster-related experiences using multivariate linear regression analyses. We used the interaction term of residential area and distrust in the government to explore the difference in the association between the respondents in Fukushima prefecture and those in the Kanto area. RESULTS: Valid responses were obtained from 976 (36.8%) residents. Distrust in the government was associated with depressive symptoms and the association was stronger in Fukushima prefecture than in the Kanto area. CONCLUSION: The deleterious effects of distrust in the government on mental health may become more serious after a nuclear power plant accident and require careful attention during support activities in an affected area.

Onset and remission of common mental disorders among adults living in temporary housing for three years after the triple disaster in Northeast Japan: comparisons with the general population.

BACKGROUND: People living in temporary housing for long periods after a disaster are at risk of poor mental health. This study investigated the post-disaster incidence and remission of common mental disorders among adults living in temporary housing for the 3 years following the 2011 Great East Japan Earthquake. METHODS: Three years after the disaster, face-to-face interviews were conducted with 1089 adult residents living in temporary housing in the disaster area, i.e., the shelter group, and a random sample of 852 community residents from non-disaster areas of East Japan. The World Health Organization Composite International Diagnostic Interview was used to diagnose DSM-IV mood, anxiety, and alcohol use disorders. Information on demographic variables and disaster experiences was also collected. RESULTS: Response rates were 49 and 46% for the shelter group and the community residents, respectively. The incidence of mood/anxiety disorder in the shelter group was elevated only in the first year post-disaster compared to that of the general population. The rate of remission for mood and anxiety disorders was significantly lower in the shelter group than in the community residents. The proportion seeking medical treatment was higher in the shelter group. CONCLUSIONS: The onset of common mental disorders increased in the first year, but then levelled off in the following years among residents in temporary housing after the disaster. Remission from incident post-disaster mental disorders was slower in the shelter group than in the general population. Post-disaster mental health service could consider the greater incidence in the first year and prolonged remission of mental disorders among survivors with a long-term stay in temporary housing after a disaster.

Long-lasting effects of distrust in government and science on mental health eight years after the Fukushima nuclear power plant disaster.

We aimed to explore the effects of erosion of trust in authorities on the long-term mental health of community residents after the 2011 Fukushima nuclear power plant accident in Japan. We investigated the effects of distrust in authorities on mental health in a cohort study following non-evacuee community residents after the 2011 Fukushima nuclear power plant accident. A baseline questionnaire survey was administered five years after the accident for a random sample of 4900 residents outside the evacuation zone in Fukushima. Distrust in the national government and in science were assessed using a four-point single-item scale. Psychological distress was measured using the K6. Posttraumatic stress symptoms were measured using an abbreviated version of the Posttraumatic Stress Disorder Checklist-Specific version. Longitudinal associations of distrust in the government and science at baseline and psychological distress and posttraumatic stress symptoms eight years after the accident were examined, controlling for the baseline level of distress or symptoms using multivariate logistic regression analyses. Valid responses were obtained from 927 (18.9%) residents. Distrust in the government at baseline was significantly associated with posttraumatic stress symptoms at follow-up, albeit controlling for baseline symptoms. While distrust in the government was also associated with psychological distress at follow-up, the association became non-significant after controlling for baseline distress. Distrust in science at baseline was not associated with posttraumatic stress symptoms or psychological distress at follow-up. Distrust in government after a nuclear power plant accident may have adverse effects on mental health in the long-term.

Learning experiences and identity development of Japanese nursing students through study abroad: a qualitative analysis.

OBJECTIVES: This study aimed to qualitatively analyze the experiences and perceptions of students at a nursing college in Japan who studied abroad in Asia and North America, thereby identifying the full range of benefits of study abroad programs for Japanese nursing students. METHODS: We conducted a qualitative analysis of the reflection papers and free-response questionnaire items completed by 50 Japanese undergraduate nursing students who participated in 9 study abroad programs in Asia and North America. Content analysis of the data proceeded from typological and deductive to data-driven and inductive, recursively and collaboratively. RESULTS: The results reveal perceived benefits in the areas of English language proficiency and motivation; knowledge of nursing practices, healthcare systems, and global health; cultural awareness and sensitivity; and various types of identity development (second-language motivation and identity, national/ethnic identity, professional identity, identity as a global citizen, and personal growth). It was also shown that students' perceptions of what they learned or gained varied according to the specific characteristics of each study abroad program. CONCLUSIONS: Study abroad experiences are often critical turning points that enhance nursing students' identity formation in the context of multiple and overlapping communities of practice. They also enhance core elements of the educational mission of a nursing college, particularly relating to liberal arts and internationalization. These findings can inform the development of assessment tools to be used in conjunction with study abroad programs at nursing colleges.

A Literature Review on Psychosocial Support for Disaster Responders: Qualitative Synthesis with Recommended Actions for Protecting and Promoting the Mental Health of Responders.

Little scientific evidence exists on ways to decrease the psychological stress experienced by disaster responders, or how to maintain and improve their mental health. In an effort to grasp the current state of research, we examined research papers, agency reports, the manuals of aid organisations, and educational materials, in both English and Japanese. Using MEDLINE, Ichushi-Web (Japanese search engine), Google Scholar, websites of the United Nations agencies, and the database of the Grants System for Japan's Ministry of Health, Labour, and Welfare, 71 pertinent materials were identified, 49 of which were analysed. As a result, 55 actions were extracted that could potentially protect and improve the mental health of disaster responders, leading to specific recommendations. These include (1) during the pre-activity phase, enabling responders to anticipate stressful situations at a disaster site and preparing them to monitor their stress level; (2) during the activity phase, engaging in preventive measures against on-site stress; (3) using external professional support when the level of stress is excessive; and (4) after the disaster response, getting back to routines, sharing of experiences, and long-term follow-up. Our results highlighted the need to offer psychological support to disaster responders throughout the various phases of their duties.

Association of response rate and prevalence estimates of common mental disorders across 129 areas in a nationally representative survey of adults in Japan.

OBJECTIVE: To investigate the association of area response rate with prevalence estimates of mental disorders in the 2nd World Mental Health Survey (WMHJ2). METHODS: The sample of the WMHJ2 was selected from community residents in 129 areas from three regions of Japan. The surveys were conducted between 2013 and 2015, and 2450 (43.4%) responded. Mental disorders as well as three disorder classes (mood, anxiety, and substance use disorders) were identified using the WHO CIDI/DSM-IV. Response rates and 12-month and lifetime prevalences were calculated for each area. A generalized linear mixed model analysis was conducted to associate area response rate with the prevalence of mental disorders, controlling for sex, age, urbanity, and geographical region. RESULTS: Area response rates ranged from 0.05 to 0.80 across the 129 areas. Area response rate was not significantly associated with 12-month or lifetime prevalence of mental disorder. Lifetime prevalences of substance use disorder were significantly lower in a survey with a higher response rate than a survey of the same area with a lower response rate. CONCLUSION: Response rate may not strongly affect the prevalence estimates of mental disorders in a community-based survey of the prevalence of common mental disorders during a particular time frame. However, a lower response rate could be associated with overestimation of lifetime prevalence of substance use disorder. This needs further elucidation.

Psychotic Experiences and Hikikomori in a Nationally Representative Sample of Adult Community Residents in Japan: A Cross-Sectional Study.

Psychotic experiences (PEs) may be associated with hikikomori. In the present study, we analyzed interview data from a community-based representative sample (N = 1,616) in Japan to know the association of PEs over a life time, as well as the two components, hallucinatory experiences (HEs) and delusional experiences (DEs), with lifetime experience of hikikomori (severe social withdrawal). Logistic regression analysis was used to estimate the association between any PE, any HE, and any DE; and hikikomori, adjusting for socio-demographics and other psychopathologies (mental disorder in the past 12 months or having autistic spectrum disorder trait). Any PE was significantly associated with hikikomori [odds ratio (OR) =3.44, 95% CI = 1.14-10.33] after adjustment for sociodemographic factors, although the association attenuated after adjusting for other psychopathologies. Any DE remained significantly associated with hikikomori, even after adjustment for all the covariates (OR = 10.50, 95% CI = 1.57-70.29). Any HE was not significantly associated with hikikomori. DEs may be associated with hikikomori. However, because the study sample was small and the temporal association between DEs and hikikomori was unclear, a future study is needed to examine a causal relationship between DEs and hikikomori.