Hikikomori: A perspective from bibliometric analysis

Validation of the German version of the 25-item hikikomori questionnaire 25

OBJECTIVES

The 25-item Hikikomori Questionnaire (HQ-25) is an instrument developed to measure a condition characterized by extreme social withdrawal that was first described in Japan. This study aimed to translate the HQ-25 into German and validate the German version (HQ-25-G).

METHODS

Translation was conducted according to established guidelines. Validation was based on data from a quota sample of individuals living in Germany, ranging from 18 to 74 years old (representing the distribution of age, sex and federal state, n = 5000). Data collection occurred during August and September 2023. We tested reliability, construct validity and concurrent validity. Moreover, HQ-25 scores for key sociodemographic group were reported.

RESULTS

Internal reliability for the HQ-25-G was excellent (Cronbach's alpha = 0.93). We confirmed the original three-factor model. Moreover, higher hikikomori levels were significantly associated with more depressive symptoms (r = 0.50), more anxiety symptoms (r = 0.45), higher loneliness levels (r = 0.56), higher levels of objective social isolation (r = -0.47), higher levels of perceived social isolation (r = 0.59) and a higher preference for solitude (r = 0.45).

CONCLUSIONS

In a large population-based sample (including younger adults, middle-aged adults and older adults), the HQ-25-G version proves to be a psychometrically robust instrument, which is useful for further exploring the phenomenon of hikikomori within the German-speaking population.

Shifting the paradigm of social withdrawal: a new era of coexisting pathological and non-pathological hikikomori

PURPOSE OF REVIEW

Social withdrawal syndrome, known as "hikikomori," has been highlighted since the late 1990 s in Japan. Hikikomori is more common in urban areas, and often comorbid with mental disorders, and now spreading throughout the world. In the post-COVID-19 era, not outing is no longer considered pathological in itself as the "new normal," and a novel concept of hikikomori is needed. This review summarizes the concept of hikikomori, and presents the latest methods for identification of hikikomori.

RECENT FINDINGS

The novel definition can distinguish between pathological and non-pathological hikikomori using the scale of "Hikikomori Diagnostic Evaluation (HiDE)," which has been developed in the hikikomori research lab at Kyushu University. An online survey among non-working adults has revealed that persons who have become pathological hikikomori for less than three months showed a particularly strong tendency toward gaming disorder and depression.

SUMMARY

Now, physical isolation itself is not pathological, but when dysfunction and distress are present, rapid mental health support should be provided. In the novel urban society, the establishment of a checkup system to assess whether persons who stay home are happy or suffering is important for prevention against mental disorders triggered by social isolation.