Validation of the Ten-Item Internet Gaming Disorder Test (IGDT-10) based on the clinical diagnosis of IGD in Japan.

Background and aims: Although the Ten-Item Internet Gaming Disorder Test (IGDT-10) has been translated into Japanese and widely used, the Japanese version has not previously been validated. We used the clinical diagnosis of IGD as a gold standard for validating the test. Methods: The Japanese version was validated using 244 gamers drawn from the general young population in Japan. Expert interviews using the Japanese version of the Structured Clinical Interview for Internet Gaming Disorder evaluated diagnoses of Internet gaming disorder (IGD). This resulted in a diagnosis of IGD for eight individuals, categorized as the gold standard group. The screening performance of the two Japanese versions with different scoring conditions was examined: the scoring method proposed by the original study (original version) and a less stringent scoring method where responses of either "often" or "sometimes" were regarded as affirmative (modified version). Results: The results of the sensitivity and specificity analyses, the Cronbach's alpha and the receiver operating characteristics analysis revealed a higher screening performance for the modified versus the original version. The optimum cutoff for the modified version was 5 or more - the sensitivity, specificity, and Youden's index were 87.5, 85.2, and 72.7%, respectively. The rate of probable IGD using the original and modified versions were 1.8% and 11.3%, respectively. Discussion and conclusion: A less stringent scoring method for the Japanese version of IGDT-10 showed a higher screening performance than the original scoring method. Future studies comprising different ethnic groups and gaming cultures should further examine the suggested scoring method.

Change of Internet Use and Bedtime among Junior High School Students after Long-Term School Closure Due to the Coronavirus Disease 2019 Pandemic.

Most schools in Japan were closed in spring 2020 due to the novel coronavirus disease 2019 (COVID-19) pandemic. We investigated lifestyle and internet use among junior high school students across eight schools after long-term school closure and compared the data with those we obtained from previous surveys. In the summers of 2018, 2019, and 2020, we conducted questionnaire surveys on seventh-grade students from the same schools. In total, 2270 participants were analyzed. All questionnaires included items regarding background, bedtime, and internet use. The participants of the 2020 survey had significantly less sleepiness during classes and longer internet use times compared with those of the previous surveys. In the 2020 survey, the rate of problematic internet use (Young's Diagnostic Questionnaire score, ≥5) was not significantly different from the results of previous surveys. The COVID-19 pandemic might have strongly influenced the sleepiness experienced by students in classes and increased the time spent using the internet since the summer of 2020. Our results indicate the need for attempts to encourage students to improve their sleep habits and moderate their media use.

Development and validation of a nine-item short screening test for ICD-11 gaming disorder (GAMES test) and estimation of the prevalence in the general young population.

BACKGROUND AND AIMS: A definition of gaming disorder (GD) was introduced in ICD-11. The purpose of this study was to develop a short screening test for GD, utilizing a reference GD group. It also sought to estimate the prevalence of GD among individuals, representative of the general young population in Japan. METHODS: Two hundred eighty one men and women selected from the general population, aged between 10 and 29 years, and 44 treatment seekers at our center completed a self-reported questionnaire comprising candidate questions for the screening test. The reference group with ICD-11 GD was established, based on face-to-face interviews with behavioral addiction experts, using a diagnostic interview instrument. The questions in the screening test were selected to best differentiate those who had GD from those who did not, and the cutoff value was determined using the Youden index. RESULTS: A nine-item screening test (GAMES test) was developed. The sensitivity and specificity of the test were both 98% and the positive predictive value in the study sample was 91%. The GAMES test comprised two factors, showed high internal consistency and was highly reproducible. The estimated prevalence of GD among the general young population was 7.6% (95% confidence interval; 6.6-8.7%) for males and 2.5% (1.9-3.2%) for females, with a combined prevalence of 5.1% (4.5-5.8%). DISCUSSION AND CONCLUSION: The GAMES test shows high validity and reliability for screening of ICD-11 GD. The estimated prevalence of 5.1% among the general young population was comparable to the pooled estimates of young people globally.

Application of the eleventh revision of the International Classification of Diseases gaming disorder criteria to treatment-seeking patients: Comparison with the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders Internet gaming disorder criteria.

BACKGROUND AND AIMS: The World Health Organization included gaming disorder (GD) in the eleventh revision of International Classification of Diseases in 2019. Due to the lack of diagnostic tools for GD, a definition has not been adequately applied. Therefore, this study aimed to apply an operationalized definition of GD to treatment-seekers. The relationship between the diagnoses of GD and Internet gaming disorder (IGD) in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders was also examined. Methods: Study participants comprised 241 treatment-seekers who had engaged in excessive gaming and experienced related problems. Psychiatrists applied the GD diagnostic criteria to the participants using a diagnostic form developed for this study. Information on gaming behavior and functional impairment was obtained through face-to-face interviews conducted by clinical psychologists. Results: In total, 78.4 and 83.0% of the participants fulfilled the GD and IGD diagnostic criteria, respectively. The sensitivity and specificity of GD diagnosis were both high when the IGD diagnosis was used as the gold standard. Participants with GD preferred online PC and console games, spent significantly more time gaming, and showed a higher level of functional impairment compared to those who did not fulfill the GD diagnostic criteria. Discussion and Conclusion: The definition of GD can be successfully applied to treatment-seekers with excessive gaming and related problems. A high concordance of GD and IGD diagnoses was found in those participants with relatively severe symptoms. The development and validation of a diagnostic tool for GD should be explored in future studies.

Relationship between problematic gaming and age at the onset of habitual gaming.

BACKGROUND: Some studies have revealed that a substantial proportion of the younger population has engaged in problematic gaming with even infants recently being able to enjoy video games. However, the relationship between the risk for problematic gaming and age at which habitual gaming starts remains unknown. This study therefore investigated this relationship among adolescents. METHODS: A survey was conducted at eight public junior high schools across Japan. The questionnaire included items regarding the background, night-time sleep, age at which weekly gaming began, time spent on the Internet and gaming, the Japanese version of Young's Diagnostic Questionnaire, the Ten-Item Internet Gaming Disorder Test (IGDT-10), and others. We analyzed 549 participants who engaged in weekly gaming and have played games during the past year. RESULTS: Among the participants, 1.8% were suspected to have Internet gaming disorder (IGDT-10 ≥ 5). Bedtime and wake-up time on weekdays and holidays were significantly later among problematic gamers (IGDT-10 ≥ 3) than among normal gamers (IGDT-10 ≤ 2). Onset of weekly gaming before the age of 5 was associated with a significantly higher risk of problematic gaming than onset of weekly gaming after the age of 10. CONCLUSIONS: Our results revealed that the risk for problematic gaming was positively associated with a younger age at which weekly gaming begins. Longitudinal problematic gaming prevention, starting from an early stage, is thus necessary.

Relationship between problematic Internet use and age at initial weekly Internet use

Background and Aims: An important proportion of infants and adolescents in Japan are using Internet-equipped devices, including smartphones, tablets, and game consoles. However, the relationship between the risk of IA and the age at initial habitual Internet use remains unknown. We aimed to investigate this relationship among adolescents. Methods: We surveyed 1,775 subjects in seven public junior high schools in Kanagawa prefecture, Japan, in November 2017. Students were asked to complete the Young's Diagnostic Questionnaire (YDQ), which captured information regarding gender, school grade, night sleep, age at which they first started using the Internet at least once weekly, Internet usage situation, and Internet use time for purposes other than study. Data from subjects who reported experience of weekly Internet use were analyzed. Results: Junior high school students who were younger at initial weekly Internet use tended to have problematic Internet use (PIU) and to spend more time on Internet activities. In particular, initial weekly Internet use before the age of five in boys was associated with a significantly increased risk of PIU (YDQ ≥ 5), with an odds ratio of 14.955, compared with initial weekly Internet use after the age of 12. Smartphone ownership significantly increased the risk of PIU compared with no ownership among the total population and among girls. Discussion and Conclusions: Junior high school male students displayed a robust relationship between initial weekly Internet use and PIU, whereas junior high school female students displayed a particularly strong relationship between smartphone ownership and PIU. Therefore, longitudinal IA preventive education from an early age is necessary.

Relationships between Internet addiction and clinicodemographic and behavioral factors.

BACKGROUNDS AND AIMS: While the Internet became an indispensable component of our contemporary life, public and academic attention is also gathered to its negative impact, namely Internet addiction (IA). Although clinicodemographic and behavioral factors are hypothetically implicated in the mechanism of IA, it still remains largely unknown how such factors are linked to IA severity. Thus, this study sought to examine relationships among IA severity and factors potentially associated with IA in Japanese students in different educational stages. METHODS: We conducted a questionnaire-based survey, which included questions about types of online activities and clinicodemographic information, the IA test for IA severity, and the K6 scale for psychological distress in 3,224 students at elementary, junior, and senior high schools, and universities. A multiple regression analysis was performed to predict IA severity with clinicodemographic and behavioral factors. RESULTS: IA severity was significantly positively related to the following factors: e-messaging, social networking services (SNS), games, holiday Internet usage, and K6 scores, while IA severity had negative correlation with using Internet for educational purposes, age of first exposure to the Internet, and sleep duration. Age was not related to IA severity among participants using both SNS and e-messaging. CONCLUSIONS: IA was linked to various online activities and the degree of psychological distress. This indicates the importance of comprehensive assessment of online behavior and psychological factors for further understanding of IA.

Inclusion of gaming disorder criteria in ICD-11: A clinical perspective in favor.

Data from a specialist treatment facility for Internet addiction (IA) in Japan showed that (a) the vast majority of treatment seekers are addicted to online games, (b) their symptoms are often quite severe, and (c) there is a significant demand for IA treatment. In addition, systemic obstacles to the delivery of medical services in Japan exist due to the exclusion of IA criteria from ICD-10. Consequently, the inclusion of GD criteria in ICD-11 will almost certainly increase the capacity and quality of treatment through advances in research and possible changes in national medical systems to meet treatment demand.

Treatment with the Self-Discovery Camp (SDiC) improves Internet gaming disorder.

INTRODUCTION: Internet gaming disorder (IGD) is a novel behavioral addiction that influences the physical, mental, and social aspects of health due to excessive Internet gaming. One type of intensive treatment for IGD is the therapeutic residential camp (TRC), which comprises many types of therapies, including psychotherapy, psychoeducational therapy, and cognitive behavioral therapy. The TRC was developed in South Korea and has been administered to many patients with IGD; however, its efficacy in other countries remains unknown. We investigated the efficacy of the Self-Discovery Camp (SDiC), a Japanese version of a TRC, and the correlations between individual characteristics and outcome measures. METHODS: We recruited 10 patients with IGD (all male, mean age=16.2years, diagnosed using the DSM-5) to spend 8 nights and 9days at the SDiC. We measured gaming time as well as self-efficacy (using the Stages of Change Readiness and Treatment Eagerness Scale, a measure of therapeutic motivation and problem recognition). RESULTS: Total gaming time was significantly lower 3months after the SDiC. Problem recognition and self-efficacy towards positive change also improved. Furthermore, there was a correlation between age of onset and problem recognition score. CONCLUSIONS: Our results demonstrate the effectiveness of the SDiC for IGD, especially regarding gaming time and self-efficacy. Additionally, age of onset may be a useful predictor of IGD prognosis. Further studies with larger sample sizes and control groups, and that target long-term outcomes, are needed to extend our understanding of SDiC efficacy.