Measuring the Quality of Life for Individuals With Prolonged Social Withdrawal (Hikikomori)

Article information

Psychiatry Investig. 2022;19(5):341-347

Publication date (electronic) : 2022 May 3

doi : https://doi.org/10.30773/pi.2021.0348

Shunsuke Nonaka^,1, Motohiro Sakai²

¹School of Child Psychology, Tokyo Future University, Tokyo, Japan

²Faculty of Education, University of Miyazaki, Miyazaki, Japan

Correspondence: Shunsuke Nonaka, PhD School of Child Psychology, Tokyo Future University, 34-12, Senjuakebono-cho, Adachi-ku, Tokyo 120-0023, Japan Tel: +81-3-5813-2540, E-mail: nonaka-shunsuke@tokyomirai.jp

Received 2021 November 16; Revised 2022 January 17; Accepted 2022 February 21.

Abstract

INTRODUCTION

Hikikomori, or prolonged social withdrawal, became known in Japan in the 1990s and is gradually becoming an international phenomenon, with cases being reported in countries/ regions such as India, Korea, USA [1], Brazil [2], China [3], Croatia [4], Hong Kong [5], Spain [6], and Ukraine [7]. Hikikomori is defined by the Japanese Ministry of Health, Labour and Welfare’s research group as a phenomenon with characteristics including avoidance of social interactions (e.g., attendance at school and work, socializing outside one’s home, staying at home on most days except solitary outings) for more than six months [8].

Most hikikomori phenomena relate to the difficulties of life of those who experience it. People with hikikomori have difficulties in interpersonal relationships [9-11], and 80.3% of those who utilized mental health welfare services were diagnosed with other psychiatric disorder(s), such as mood, anxiety, personality, or developmental disorders [12]. Furthermore, severe physical problems, including nutritional disorders [13] and increased body weight and obesity may be found in hikikomori cases [14]. Some studies developed tools to assess the clinical picture of hikikomori, including psychological and behavioral characteristics [15], affinity for hikikomori [16], and social interaction [10].

Traditionally, psychosocial support for hikikomori has focused on social participation and reintegration. However, people with hikikomori do not always seek social participation, and may focus on improving their quality of life (QOL) without working [8]. Furthermore, even if their hikikomori improves and they begin to participate in society, their subjective QOL may not increase sufficiently. For these reasons, people who have experienced hikikomori and mental health professionals in Japan have repeatedly expressed that support should focus on the individual’s living difficulties rather than social participation such as employment. This opinion has been shared in media broadcasts and is gaining popularity in Japan. Thus, there is a growing social awareness that support for hikikomori should focus on reducing the person’s difficulty with living, that is, improving their QOL [17]. This requires a scale that appropriately assesses the QOL of people with hikikomori. Moreover, as the QOL of each individual with hikikomori varies largely, the variation must also be addressed. However, currently, no assessment tool focuses on the subjective QOL specific to hikikomori.

QOL is defined as an individual’s perception of their position in life based on their culture and value systems, goals, expectations, standards, and concerns [18]. Previous studies have used existing scales, which are not specific to hikikomori to assess the QOL of these individuals [7,19,20]. However, individuals with hikikomori have a different living environment than those without. For example, they do not attend school or work, do not interact with others, live with their parents, and often avoid treatment. They face difficulties in social interactions and spend a majority of their time at home. However, existing QOL scales do not measure these factors, making it difficult to adequately assess changes in QOL during hikikomori. Therefore, a tool to assess QOL specific to hikikomori is needed.

In this study, we developed a scale to assess the QOL specific to hikikomori and confirmed the psychometric properties.

METHODS

RESULTS

The mean age of the hikikomori group was 44.58 (standard deviation [SD]=9.69) years, and 70.7% of them were male. The number of days out of home was highest in the control group, followed by the previous group and the hikikomori group. Significant differences were found between the three groups in all the scales—difficulty in social participation, social interaction behaviors, hikikomori characteristics, depressive symptom, and subjective happiness (Table 1).

Table 1.

Demographics of participants

Selecting quality of life scale for hikikomori items

We excluded the three items that showed ceiling or floor effects based on the means and SDs (item 26, 2.21±0.89; item 28, 0.86±0.90; item 29, 0.78±0.80). Additionally, we excluded the two items with a coefficient lower than 0.30 by item-reminder correlations analysis.

The results of the scree plot from the EFA strongly supported a single factor, with the first eigenvalue over five times as large as that of the second factor and substantially larger than that of the others (17.49, 3.25, 2.18, 1.95, etc.). The factor loadings for the single-factor solution were all positive and ranged from 0.32 to 0.84. The Cronbach’s alphas were also high (α= 0.95) and mostly unchanged regardless of which items were deleted (0.949 to 0.952). These findings suggest that the QOLH met the unidimensionality assumption allowing us to proceed with the IRT analysis.

We analyzed the 45-items using IRT analysis to confirm discrimination and difficulty parameters. The results of IRT were discrimination parameter 0.32 to 1.47 and difficulty parameters b1=-4.40 to -0.55, b2=-1.56 to 2.06, b3=-0.55 to 5.49. Items with discrimination of less than 0.80 [29] were deleted, and finally, the QOL-H, consisting of 20 items, was developed.

Table 2 shows IRT parameters, factor loadings, and Cronbach’s α if the item is deleted from QOL-H. The results were discrimination parameter 0.85 to 1.76 and difficulty parameters b₁=-3.02 to -0.60, b₂=-0.26 to 2.22, b₃=2.39 to 5.78 (Supplementary Figure 1 in the online-only Data Supplement). Inspection of the TIF indicated that the 20-item QOL-H had greater precision at around θ=0 to 1 on the QOL trait continuum (Figure 1).

Table 2.

Item response theory parameters for the 20 items of the quality of life scale for hikikomori

Figure 1.

Total information function for the quality of life scale for hikikomori.

Reliability and validity

The Cronbach’s alpha for the QOL-H indicated high internal consistency (α=0.94). The ICC, using data from 91 participants with responses to both anchor items ranging from -3 to 3, showed high test-retest reliability (0.86; 95% confidence interval, 0.80 to 0.91).

Significant differences were found between all groups (F (2, 394)=56.75, p<0.001; Table 3). Post-hoc analyses showed that QOL-H scores were highest in the control group, followed by the previous group and the hikikomori group.

Table 3.

Means, standard deviations, analysis of variance results, and effect sizes for the 20-item quality of life scale for hikikomori

As expected, the QOL-H were significantly and positively correlated with the ABS-H-SR (r=0.57), SHS (r=0.64) and negatively correlated with HQ-25 (r=-0.42), J-PHQ-9 (r=-0.70), which confirmed the convergent validity (Table 4).

Table 4.

Correlations with the scores of the quality of life scale for hikikomori (N=199)

DISCUSSION

This study aimed to develop a scale to assess the QOL specific to hikikomori and confirm its psychometric properties, including the item trait, reliability, and validity.

The average IRT discrimination parameter was 1.19 and showed that the QOL-H had good measurement accuracy of assessing QOL of individuals who experienced hikikomori. TIF indicates that this scale has high measurement accuracy when QOL is around average or slightly high. Among the 20 items of QOL-H, item 48 (I feel that my life is meaningful) had the highest discrimination, followed by item 21 (I am satisfied with myself). This may be due to the relevance of these items to overall QOL. Items 21 and 48 showed high item difficulty in b3; a high QOL is required to score highly on these items. Item 32 (I am satisfied with my ability to work), and item 40 (I am satisfied with my sociability) had high measurement accuracy when QOL was higher than average, which may be because these items are directly related to the characteristics of hikikomori. The difficulty level of item 46 (I can take part in relaxing day-to-day activities) and item 47 (I can easily engage in activities outside my home) were relatively low compared to the other items, and there was a peak in measurement accuracy when QOL was a little low. This result may indicate that increasing the relaxing activities in one’s life may improve QOL for people with hikikomori, especially those who have low QOL.

This study indicated that QOL-H had sufficient internal consistency, test-retest reliability, and convergent validity. In the present study, we used emotional and behavioral variables to examine convergent validity, but further studies are needed to examine the relationship of QOL-H with objective functioning in life or QOL as rated by a third party such as a clinician or researcher. Furthermore, future studies should also examine whether QOL-H can sensitively reflect changes in QOL. The results of criterion-related validity suggest that QOL-H is sensitive to the differences in QOL between people who have experienced hikikomori and those who have not, and between people who currently have hikikomori and those who have recovered from it.

However, the study has some limitations. First, the sample bias cannot be denied. This study is web-based research, and web-based research has the benefit of increasing access to hikikomori people. However, people who are not familiar with the Internet would not have been included in the participants of this study. Second, the average age of the participants was over 40 years old, and there were relatively few young participants. Therefore, the findings of this study can only be interpreted in light of these characteristics of the participants in this study. Further, future studies are needed to confirm whether the findings of this study will be reflected in countries other than Japan. It should be examined whether QOL-H can measure QOL appropriately for culturally different hikikomori because their cognition or lifestyle may differ by culture even if they show similar behavioral characteristics [30]. Lastly, another limitation is that existing scales such as the Lubben Social Network Scale [31] were not used in assessing the difficulty in social participation to reduce the burden on the participants.

Psychosocial interventions for people with hikikomori should focus on QOL as well as on psychiatric symptoms and psycho-behavioral characteristics. The QOL-H developed in this study had sufficient reliability, validity, and high discrimination. The QOL-H can be useful in assessing the QOL of people with hikikomori in order to develop psychosocial intervention for people with hikikomori and monitoring its effects.

Supplementary Materials

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