Prevalence of Internet gaming disorder in German adolescents: diagnostic contribution of the nine DSM-5 criteria in a state-wide representative sample

Clarification of the Cut-off Score for Nine-Item Internet Gaming Disorder Scale-Short Form (IGDS9-SF) in a Chinese Context

BACKGROUND

The nine-item Internet Gaming Disorder Scale-Short-Form (IGDS9-SF) is a self-reported screening measure based on the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) criteria. It has been used to assesses symptoms and prevalence of Internet Gaming Disorder (IGD) in general population. Despite its widespread use, there is confusion arising from the recommended cutoff score for a positive diagnosis. This study aimed to identify the appropriate cutoff score for IGDS9-SF in a Chinese context.

METHODS

The present study included a sample from clinical settings (n = 131) and another from universities (n = 3742). IGDS9-SF measurement and structured clinical interviews based on DSM-5 criteria for IGD were conducted in the sample from clinical settings. The cutoff score was determined using the receiver operating characteristics (ROC) curve. The validity of this cutoff score was further assessed in a sample from universities.

RESULTS

Mathematical models suggest that the score of 32 is the optimal cutoff point (Youden's index, 96.2%; diagnostic accuracy, 96.1%; sensitivity, 98.0%; specificity, 91.9%; NPV, 91.9%; and NPY, 100%). The prevalence of IGD is 2.9% in this study.

CONCLUSION

This study suggested that the optimal cutoff score of IGDS9-SF is 32 for the positive diagnosis of IGD in a Chinese context.

School-Related Risk Factors of Internet Use Disorders

A growing body of research focusing on the risk factors of Internet use disorder (IUD) underlines the effect of sociodemographic variables like age and gender or comorbid mental disorders on IUD symptoms. The relation between IUD symptoms and school-related variables has to date been insufficiently studied. The present study closes this gap by investigating the relation between school-relevant factors such as absenteeism, school grades, procrastination, school-related social behavior, and learning behavior and IUD symptoms in a high-risk sample. n = 418 students between 11 and 21 years of age (M = 15.10, SD = 1.97), screened for elevated risk of IUD, participated in the study. Sociodemographic data, school grades and absent days, Internet use variables (time spent online and gaming), as well as school-related psychological variables (procrastination, learning behavior, and social behavior) were assessed via self-report questionnaires. IUD symptoms were assessed with an adapted version of the German Video Game Dependency Scale (CSAS), which is based on the 9 criteria for Internet gaming disorder in the DSM-5. The instrument was adapted to include the assessment of non-gaming IUD symptoms. Taking the hierarchical structure of the data into account, a multilevel modeling approach was used to analyze the data. Procrastination, time spent online, and gaming were significant predictors of IUD symptoms at the individual level, whereas social behavior significantly predicted symptoms of IUD at the school level. In addition to previous findings on risk factors of IUD, this study indicates the importance of school-related factors in the development of IUD, especially psychological factors that play a role in the school setting. The early age of IUD onset and the high relevance of prevention of IUD at the school age underline the relevance of this finding.

The Digital Addiction Scale for Children: Development and Validation

Researchers worldwide have developed and validated several scales to assess various forms of adults' digital addiction. The urge for some of these scales found support in World Health Organization's inclusion of gaming disorder as a mental health condition in its eleventh revision of the International Classification of Diseases in June 2018. Additionally, several studies have shown that children are starting to use digital devices (DDs) (e.g., tablets and smartphones) at a very young age, including playing video games and engaging in social media. Consequently, the need for early detection of the risk of digital addiction among children is becoming more of a necessity. In the present study, the Digital Addiction Scale for Children (DASC)-a 25-item self-report instrument-was developed and validated to assess the behavior of children 9 to 12 years old in association with DD usage, including video gaming, social media, and texting. The sample comprised 822 participants (54.2 percent males), from grade 4 to grade 7. The DASC showed excellent internal consistency reliability (α = 0.936) and adequate concurrent and criterion-related validities. The results of the confirmatory factor analysis showed that the DASC fitted the data very well. The DASC paves the way to (a) help in early identification of children at risk of problematic use of DDs and/or becoming addicted to DDs and (b) stimulate further research concerning children from different cultural and contextual settings.

Microstructural changes and internet addiction behaviour: A preliminary diffusion MRI study

Internet addiction (IA) is a major health problem and is associated with comorbidities like insomnia and depression. These consequences frequently confound neuroanatomical correlates of IA in those suffering from it. We enrolled a number of 123 healthy native German-speaking adults (53 male, mean age: 36.8 ± 18.86) from the Leipzig Study for Mind-Body-Emotion Interactions (LEMON) database, for whom diffusion MRI data, internet addiction test, brief self-control scale (SCS), coping orientations to problems experienced (COPE), and depression scores were available. DMRI connectometry was used to investigate white matter microstructural correlates of the severity of internet addiction identified through IAT, in a group of healty young individuals. A multiple regression model was adopted with age, gender, SCS total score, COPE total score, and BDI-sum as covariates to track white matter fibers in which connectivity was associated with IAT. The connectometry analysis identified a direct correlation between connectivity in the splenium of corpus callosum (CC), parts of bilateral corticospinal tracts (CST), and bilateral arcuate fasciculi (AF) (FDR = 0.0023001), and an inverse correlation of the connectivity in the genu of CC and right fornix (FDR = 0.047138), with the IAT score in healthy adults. We suggest connectivity in the CC and CST as well as fornix and AF to be considered as microstructural biomarkers of predisposition to IA in healthy population.

The Clinical Utility of the Chen Internet Addiction Scale-Gaming Version, for Internet Gaming Disorder in the DSM-5 among Young Adults

Objectives: The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) includes the diagnostic criteria for Internet gaming disorder (IGD). This study evaluated (1) the screening, diagnostic, and prevalence-estimated cutoff points of the Chen Internet Addiction Scale–Gaming Version (CIAS-G) for IGD in the DSM-5; and (2) the differences in the CIAS-G and subscale scores among individuals with IGD, regular gamers (RGs), and other control subjects. Methods: We recruited 69 participants with IGD, 69 RGs, and 69 healthy participants based on diagnostic interviews conducted by a psychiatrist according to DSM-5 IGD criteria. All participants completed the CIAS-G and were assessed using the clinical global impression scale. Results: The optimal screening and diagnostic cutoff points were 68 or more (sensitivity, 97.1%; specificity, 76.8%) and 72 or more (sensitivity, 85.5%; specificity, 87.0%) for IGD based on DSM-5 criteria, respectively. The 76 or more cutoff point had the highest number needed to misdiagnose and was the optimal prevalence estimated cutoff point. Conclusions: The screening cutoff point could be used to identify individuals with IGD for further diagnostic interviewing to confirm the diagnosis in the clinical setting or for two-stage epidemiological evaluation. The diagnostic cutoff point provides a provisional diagnosis of IGD when diagnostic interviewing is unavailable. The prevalence-estimated cutoff point could be used to estimate the prevalence of IGD in large-scale epidemiological investigations when further diagnostic interviewing is impractical. The clinical and epidemiological utility of CIAS-G warrants further study.

Laxer Clinical Criteria for Gaming Disorder May Hinder Future Efforts to Devise an Efficient Diagnostic Approach: A Tree-Based Model Study

Internet Gaming Disorder (IGD) has been recognized in May 2013 and can be evaluated using the criteria developed by American Psychiatric Association (APA). The present study investigated the role each IGD criteria plays in diagnosing disordered gaming. A total of 3377 participants (mean age 20 years, SD = 4.3 years) participated in the study. The data collected was scrutinized to detect patterns of IGD using Conditional Inference Tree (Ctree), a sophisticated machine algorithm. Participants provided basic sociodemographic information and completed the Internet Gaming Disorder Scale–Short-Form (IGDS9-SF). The results identified classes of IGD-related symptoms, indicating that endorsing ‘withdrawal’ and ‘loss of control’ increases the probability of disordered gaming by 77.77% while endorsement of ‘withdrawal’, ‘loss of control’ and ‘negative consequences’ increases the probability of disordered gaming by 26.66%. Moreover, lack of endorsement of ‘withdrawal’ and endorsement of ‘preoccupation’ increases the likelihood of disordered gaming by 7.14%. Taken together, the results obtained illustrate that different IGD criteria can present with different clinical weighing as unique diagnostic roles in the development of disordered gaming can be evidenced by each criterion. Moreover, the present findings help inform future revisions of diagnostic manuals and helps enhancing the assessment of IGD in the future. Additional research and clinical implications are discussed.

Treatments of internet gaming disorder: a systematic review of the evidence

Introduction: The American Psychiatric Association included Internet gaming disorder (IGD) in the 5th Edition of the Diagnostic and Statistical Manual of Mental Disorders, and the World Health Organization included gaming disorder in the 11th revision of the International Classification of Diseases. These recent updates suggest significant concern related to the harms of excessive gaming.Areas covered: This systematic review provides an updated summary of the scientific literature on treatments for IGD. Inclusion criteria were that studies: 1) evaluate the effectiveness of an intervention for IGD or excessive gaming; 2) use an experimental design (i.e. multi-armed [randomized or nonrandomized] or pretest-posttest); 3) include at least 10 participants per group; and 4) include an outcome measure of IGD symptoms or gaming duration. The review identified 22 studies evaluating treatments for IGD: 8 evaluating medication, 7 evaluating cognitive behavioral psychotherapy, and 7 evaluating other interventions and psychosocial treatments.Expert opinion: Even with the recent uptick in publication of such clinical trials, methodological flaws prevent strong conclusions about the efficacy of any treatment for IGD. Additional well-designed clinical trials using common metrics for assessing IGD symptoms are needed to advance the field.

The Mediating Effects of Affect on Associations between Impulsivity or Resilience and Internet Gaming Disorder

Internet gaming disorder (IGD) is a new disease proposed by the Diagnostic and Statistical Manual of Mental Disorders-Fifth Edition (DSM-5), and has been studied extensively in relation to depression and impulsivity. The relationship between resilience and disease has been found in a variety of addictive disorders, but studies on IGD are lacking. In this study, 71 IGD patients and 78 healthy controls (HCs) were recruited. Impulsivity, resilience, affects, and the degree of internet game addiction were measured using formal tools. The measured values were analyzed by mediation analysis to evaluate the mediating role of affects on resilience and impulsivity related to IGD symptoms. The IGD group showed higher impulsivity, lower resilience, lower positive affect, and higher negative affect than the HC group. The mediation analysis showed that a positive affect was a mediator between impulsivity and the severity of addiction in both groups. Negative affect mediated impulsivity/resilience and the severity of addiction only in the IGD group. Although the results of this study are based on a narrow category of subjects, who are young male adults around 25 years of age, the results suggest that positive affect can be strengthened to prevent the IGD illness, and that illness symptoms may be alleviated by reducing negative affect.

Research progress and debates on gaming disorder

Gaming disorder has become a significant issue in mental healthcare. While gaming is an important form of entertainment, excessive gaming may cause serious consequences for players. At present, there are still controversies in the academic community concerning the public health problems related to gaming disorder. This article attempts to expound the definition, epidemiology, aetiology, diagnosis, treatment and prevention of gaming disorder, in order to contribute to future conceptualization of gaming disorder.

Performance of the DSM-5-based criteria for Internet addiction: A factor analytical examination of three samples

BACKGROUND AND AIMS

The diagnosis "Internet Gaming Disorder" (IGD) has been included in the fifth edition of Diagnostic and Statistical Manual of Mental Disorders. However, the nine criteria have not been sufficiently reviewed for their diagnostic value. This study focuses on a broader approach of Internet addiction (IA) including other Internet activities. It is not yet clear what the construct of IA is in terms of dimensionality and homogeneity and how the individual criteria contribute to explained variance.

METHODS

Three separate exploratory factor analyses and multinomial logistic regression analyses were carried out based on information collected from a general population-based sample (n = 196), a sample of people recruited at job centers (n = 138), and a student sample (n = 188).

RESULTS

Both of the adult samples show a distinct single-factor solution. The analysis of the student sample suggests a two-factor solution. Only one item (criterion 8: escape from a negative mood) can be assigned to the second factor. Altogether, high endorsement rates of the eighth criterion in all three samples indicate low discriminatory power.

DISCUSSION AND CONCLUSIONS

Overall, the analysis shows that the construct of IA is represented one dimensionally by the diagnostic criteria of the IGD. However, the student sample indicates evidence of age-specific performance of the criteria. The criterion "Escape from a negative mood" might be insufficient in discriminating between problematic and non-problematic Internet use. The findings deserve further examination, in particular with respect to the performance of the criteria in different age groups as well as in non-preselected samples.

Evaluating an Internet Gaming Disorder Scale Using Mokken Scaling Analysis

Internet Gaming Disorder (IGD) was recently included as a condition for further study in the fifth and latest version of the Diagnostic and Statistical Manual of Mental Disorders. The present study investigated whether the IGD criteria comprise a unidimensional construct. Data stemmed from a sample of Norwegians aged 17.5 years in 2012 and 19.5 years in 2014 (N = 1258). The study used the Mokken scale analysis to investigate whether the score of the different items on the IGD scale measured a single latent variable and if the scale functions differently for males and females. Correlation analysis was conducted between the scores on the IGD scale (count) and the Gaming Addiction Scale for Adolescents (GASA, categorical), both assessed in 2014. Negative binomial regression analyses were applied in order to investigate how different predictors of mental health assessed in 2012 were associated with IGD assessed in 2014. The Mokken scale analysis showed that all item-coefficients of homogeneity exceeded 0.3 when the whole sample completed the scale and when females completed the scale, indicating that the items reflect a single latent variable. In both cases moderate (H > 0.40) unidimensionality was shown. The item measuring "tolerance" did not exceed 0.3 in the scale when completed by males, indicating that only eight out of nine items reflect a single latent variable when applied to males only. The eight-item scale containing males showed weak (H > 0.30) unidimensionality. The correlation analysis showed a positive correlation between the scores on the IGD scale and the GASA (r = 0.71, p < 0.01) when assessed simultaneously and a positive but lower correlation (r = 0.48, p < 0.01) when assessed longitudinally. Results from the negative binomial regression analysis showed that previous video-game addiction, being male, depression, aggression and loneliness were significant predictors of IGD. The associations were small for all independent variables except previous video game addiction and gender where the associations were large. Although the results from the correlation analysis and regression analysis showed predictive validity of the scale, the results from the Mokken analysis suggest that the IGD scale may not be applied as a unidimensional scale when the tolerance item is included.

Lipidomic profiles disturbed by the internet gaming disorder in young Korean males

Internet Gaming Disorder (IGD) is characterized by uncontrollable and persistent playing of internet games despite the occurrence of negative consequences. Although there is a worldwide treatment demand, IGD still doesn't have an explicit biomarker. The primary goal of the study is to characterize lipidomic profiles specific to internet gaming disorder (IGD) based on liquid-chromatography Orbitrap mass-spectrometry (LC Orbitrap MS). Primarily, a total of 19 lipids were significantly dys-regulated in the IGD group compared to healthy controls. The lipidomic feature was mainly characterized by various types of phosphatidylcholines (PCs) and lyso-phosphatidylcholines (LysoPCs). Subsequent multivariate statistical model and linear regression model prioritized two LysoPCs (C16:0 and C18:0) for potential biomarker. Receiver operating characteristic (ROC) analysis demonstrated excellent performance of the combined lipid set for discriminating the IGD group from healthy controls (AUC: 0.981, 95% confidence interval: 0.958-1.000). Additional evaluation with potential confounders and clinical parameters suggested robustness and potential applicability of the outcome as biomarkers which may aid diagnosis.

Perceptions of U.S. and Canadian maple syrup producers toward climate change, its impacts, and potential adaptation measures

The production of maple syrup is an important cultural and economic activity directly related to the climate of northeastern North America. As a result, there are signs that climate change could have negative impacts on maple syrup production in the next decades, particularly for regions located at the southern margins of the sugar maple (Acer saccharum Marsh.) range. The purpose of this survey study is to present the beliefs and opinions of maple syrup producers of Canada (N = 241) and the U.S. (N = 113) on climate change in general, its impacts on sugar maple health and maple syrup production, and potential adaptation measures. Using conditional inference classification trees, we examined how the socio-economic profile of respondents and the geographic location and size of respondents' sugar bushes shaped the responses of survey participants. While a majority (75%) of respondents are confident that the average temperature on Earth is increasing, less than half (46%) believe that climate change will have negative impacts on maple syrup yield in the next 30 years. Political view was a significant predictor of these results, with respondents at the right right and center-right of the political spectrum being less likely to believe in climate change and less likely to anticipate negative effects of climate change on maple syrup production. In addition, 77% of the participants indicated an interest in adopting adaptation strategies if those could increase maple syrup production. This interest was greater for respondents using vacuum tubing for sap collection than other collection methods. However, for many respondents (particularly in Canada), lack of information was identified as a constraint limiting adaptation to climate change.

Internet Gaming Disorder and Its Associated Personality Traits: A Systematic Review Using PRISMA Guidelines

For most individuals, videogame playing is a fun and enjoyable activity that brings many benefits. However, for a small minority, the activity can be problematic and has led to much research into “gaming disorder.” In explanations concerning the contributory factors to gaming disorder, personality traits have been increasingly studied. The present paper carried out a systematic review of available literature using Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. The inclusion criteria were (i) publication date between 2000 and 2018, (ii) being an empirical study, (iii) written in English and Turkish languages (the two languages spoken by the authors), (iv) published in a scholarly peer-reviewed journal, and (v) conducted an assessment of IGD and personality traits objectively. Studies were excluded from the review if they were (i) single-case studies, (ii) unpublished thesis and dissertation studies, and (iii) not published in a peer-reviewed journal. Following these procedures, 21 eligible empirical studies were included. Results demonstrated that 24 distinct personality traits had been examined in relation to IGD and that some of these traits were demonstrated as risk factors for gaming addiction (although not always in the same direction).

Game of thorns: Modern day opium

With the advent of internet and mobile communication the virtual space of world wide web has become a playground; people plugged in to it at distant horizon completely unfamiliar to each other are players; keyboard, touchpad and joysticks have become the tools of play; webmaster, app developer are self designated referees of the game; while the virtual media is the largest ever spectators in this amphitheatre of the web. More and more youth are getting hooked onto this and are gradually becoming dependent on these games. World Health Organization has recognized this as a diagnosable medical illness and included as Internet Gaming Disorder (IGD) in its International Classification of Diseases (ICD) -11 released in 2018. Various aspects of this problem are discussed in this article.

Psychometric properties of the Internet Gaming Disorder Test (IGDT-10) and problematic gaming behavior among Finnish vocational school students

This study was conducted to investigate the psychometric properties of the Finnish version of the Internet Gaming Disorder Test (IGDT-10), identify the proportion displaying problematic gaming behavior (PGB) among Finnish vocational school students, and characterize the relationships between sociodemographic factors and gaming characteristics predicting PGB in this population. This cross-sectional study involving 773 students (mean age 17.5 years). Socio-demographic and gaming behavior characteristics were established using a web-based survey. A confirmatory factor analysis (CFA) showed that the IGDT-10 test has appropriate psychometric properties. The proportion of students exhibiting PGB based on the DSM-5 cut-off threshold was 1.3%. Regression analysis showed that male gender, preference for gaming on a personal computer, gaming time, poor self-perceived health status, and a preference for the solo and multiplayer online battle arenas (MOBA) game genres related positively to PGB scores. These findings demonstrate the appropriateness of the IGDT-10 test for the assessment of problematic gaming among adults, and support further research on PGB in Finland.

A clinical evaluation of the DSM-5 criteria for Internet Gaming Disorder and a pilot study on their applicability to further Internet-related disorders

BACKGROUND AND AIMS

Internet Gaming Disorder (IGD) and other Internet-related disorders (IRDs) have become growing health concerns in our today's lives. Based on defined diagnostic criteria, IGD has been recognized as a condition for further research in the DSM-5; however, other IRDs have been excluded. Since the release of the DSM-5, representativeness and appropriateness of the nine diagnostic criteria have been debated. Although some first evidence has been published to evaluate these criteria, our knowledge is still limited. Thus, the purpose of this study was to provide data on the clinical validity of the DSM-5 criteria for IGD and other types of IRD. We were also interested in examining the additional diagnostic validity of craving that is currently not being considered in the DSM-5.

METHODS

Analyses on a sample of n = 166 treatment seekers for IRDs were performed. The clinician's diagnosis was used as a main reference for determining the DSM criteria's diagnostic performance. Secondary criteria (depression and anxiety) were defined as indicators for the construct validity.

RESULTS

The overall diagnostic accuracy ranged between 76.6% for deceiving and 92% for loss of control and craving. Considerable differences occurred in the degree of sensitivity and specificity between the single criteria. No particular differences were found for the applicability of the criteria to other forms of IRDs.

DISCUSSION AND CONCLUSIONS

Our results confirm the validity of the DSM criteria. However, the diagnostic utility of the criterion escaping aversive moods is critically discussed. Considering craving as an additional diagnostic indicator might be recommendable.

Bio-psychosocial factors of children and adolescents with internet gaming disorder: a systematic review

Previous large-scale studies suggest that internet gaming disorder (IGD) among children and adolescents has become an important public concern. Minors are known to be particularly susceptible to problematic internet gaming use owing to age-related underdevelopment of cognitive control. It has been shown that precursors of addictions appear during adolescence; therefore, prevention efforts must be established targeting minors who have their first experience with addictive substances and behaviors during pubescence. Since the DSM-5 classification of IGD in 2013, studies on IGD have drastically increased in number. Thus, we performed an updated review of studies of IGD in children and adolescents to assess the clinical implications of IGD. The search included all publication years, using PubMed, MEDLINE, and PsycINFO. Across studies, the presence of IGD had a negative effect on sleep and schoolwork in minors. Additionally, family factors, including the quality of parent-child relationships, were important social factors in minors with IGD. Brain imaging studies indicate that impaired cognitive control in minors with IGD is associated with abnormal function in the prefrontal cortex and striatum. Persistent pathological online game use from childhood may aggravate abnormal brain function; therefore, preventive care and early intervention are increasingly important. Although extant research supports the effectiveness of cognitive behavioral therapy for minors with IGD, effective psychological intervention for minors with IGD is an urgent issue that requires further research. This review, which presents updated findings of IGD in minors, is expected to contribute to the development of future research and be useful in clinical practice in the field of child and adolescent psychiatry.

Females are more vulnerable to Internet gaming disorder than males: Evidence from cortical thickness abnormalities

BACKGROUND

Male predominance is a well-known feature of Internet gaming disorder (IGD), with a reported male to female ratio of 3:1. Because of the overwhelming focus on males, little is known about the neural basis of sex differences in IGD, especially neuroanatomical features. Thus, investigations on sex differences with an adequate sample size are critical for improving the understanding of biological mechanisms underlying IGD.

METHODS

Structural magnetic resonance imaging data were acquired from 62 IGD subjects (29 males, 33 females) and 71 recreational game users (RGUs) (37 males, 34 females) with well-matched age and education levels. Group-by-sex interaction in cortical thickness was analyzed, and the correlations between cortical thickness and addiction severity were calculated.

RESULTS

We detected a group-by-sex interaction in the bilateral rostral middle frontal gyri (MFG), left superior frontal gyrus (SFG), left supramarginal gyrus (SMG), right posterior cingulate cortex (PCC), and right superior parietal lobule (SPL). Post-hoc analyses revealed that, compared with same-sex RGUs, male IGD subjects had increased cortical thickness and female IGD subjects had reduced cortical thickness beside their right PCC. By contrast, male IGD subjects had reduced cortical thickness and female IGD subjects had increased cortical thickness in their right PCC. Moreover, only females showed significant negative correlations between the cortical thickness and their self-reported cravings and Internet addiction test scores.

CONCLUSIONS

For female IGD subjects, the reduced cortical thickness, combined with the negative correlations of addiction severities, suggests the great effect created by IGD in the brain regions. Males and females may be affected differently by IGD, with females being more vulnerable to it.

The relative contribution of motives and maladaptive cognitions to levels of Internet Gaming Disorder

This study aimed at determining whether motives and/or maladaptive cognitions would predict levels of Internet Gaming Disorder independently of negative affect and problematic Internet use. Seventy-nine Internet gamers completed the following questionnaires: Ten-Item Internet Gaming Disorder Test, Problematic Internet Use Questionnaire Short Form, Depression Anxiety and Stress Scale 21, Motives for Online Gaming Questionnaire, and Maladaptive Gaming-Related Cognitions Scale. Results showed that all variables were positively and significantly correlated with levels of Internet Gaming Disorder with the exception of motives relating to recreation. Furthermore, a hierarchical linear regression analysis showed that motives relating to coping and skills development and maladaptive cognitions relating to overvaluing of game rewards were the only significant predictors of levels of Internet Gaming Disorder when controlling for negative affect and problematic Internet use. The implications of these findings are discussed.

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Motives and maladaptive cognitions predict levels of IGD.

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Motives relating to coping skills development and maladaptive cognitions relating to overvaluing game rewards were the strongest predictors of IGD.

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Findings were independent of negative affect and problematic Internet use.

A longitudinal study on psychosocial causes and consequences of Internet gaming disorder in adolescence

BACKGROUND

In 2013, Internet gaming disorder (IGD) was incorporated in the current version of the DSM-5. IGD refers to a problematic use of video games. Longitudinal studies on the etiology of IGD are lacking. Furthermore, it is currently unclear to which extent associated psychopathological problems are causes or consequences of IGD. In the present survey, longitudinal associations between IGD and adolescent and parental mental health were investigated for the first time, as well as the temporal stability of IGD.

METHODS

In a cross-lagged panel design study, family dyads (adolescent with a parent each) were examined in 2016 (t1) and again 1 year later (2017, t2). Overall, 1095 family dyads were assessed at t1 and 985 dyads were re-assessed at t2 with standardized measures of IGD and several aspects of adolescent and parental mental health. Data were analyzed with structural equation modeling (SEM).

RESULTS

Male gender, a higher level of hyperactivity/inattention, self-esteem problems and IGD at t1 were predictors of IGD at t2. IGD at t1 was a predictor for adolescent emotional distress at t2. Overall, 357 out of the 985 adolescents received a diagnosis of IGD at t1 or t2: 142 (14.4%) at t1 and t2, 100 (10.2%) only at t1, and 115 (11.7%) only at t2.

CONCLUSIONS

Hyperactivity/inattention and self-esteem problems seem to be important for the development of IGD. We found first empirical evidence that IGD could prospectively contribute to a deterioration of adolescent mental health. Only a subgroup of affected adolescents showed IGD consistently over 1 year.

The Role of Cognitive Emotion Regulation Strategies in Problem Gaming Among Adolescents: A Nationally Representative Survey Study

Explanatory theoretical models have proposed an association between problematic online gaming and abilities or strategies in alleviating distress or negative emotions in times of stress as proximal non-gaming-related personality factors. However, there is little research that has targeted how emotion regulation relates to problematic online gaming-especially during adolescence when gaming behavior is most prevalent. In emotion regulation research, there has been a particular emphasis on rumination because it is strongly associated with overall psychopathology. However, it is unknown whether this putatively maladaptive strategy relates to problematic online gaming and whether it is a gender-dependent association. Consequently, the present study examined how emotion regulation strategies, and particularly rumination, related to problem gaming and tested whether gender moderated this relationship in adolescents. In a national representative adolescent sample, 46.9% of the participants (N = 1,646) reported online gaming in the past 12 months and provided information on problematic gaming, and it was these data that were used for further analysis. Their data concerning problematic online gaming and emotion regulation strategies were analyzed, including rumination along with other putatively maladaptive (e.g., catastrophizing) and adaptive (e.g., positive reappraisal) strategies, while controlling for age, gender, and game genre preference. Results of linear regression analyses showed that all the putatively maladaptive emotion regulation strategies (including self-blame, other blame, catastrophizing, and rumination) were positively related to problematic online gaming. Positive reappraisal proved to be a protective factor; it was inversely related to problematic online gaming. In addition, the relationship between rumination and online gaming was moderated by gender (i.e., the relationship was stronger among boys). Based on the results, it is argued that emotion regulation is a useful framework to study problematic online gaming. The present study highlighted that the relative predictive value of rumination for problematic online gaming varied for boys and girls, suggesting that trait rumination might be a gender-specific vulnerability factor for problematic online gaming, but this requires further investigation and replication.

The role of self-esteem in Internet addiction within the context of comorbid mental disorders: Findings from a general population-based sample

BACKGROUND AND AIMS

Internet Addiction (IA) has consistently been related to comorbid psychiatric disorders and lowered self-esteem. However, most studies relied on self-report questionnaires using non-representative samples. This study aims to analyze the relative impact of self-esteem and comorbid psychopathology with lifetime IA in a population-based sample of excessive Internet users using clinical diagnoses assessed in a personal interview.

METHODS

The sample of this study is based on a general population survey. Using the Compulsive Internet Use Scale, all participants with elevated Internet use scores were selected and invited to a follow-up interview. Current DSM-5 criteria for Internet gaming disorder were rephrased to apply to all Internet activities. Out of 196 participants, 82 fulfilled the criteria for IA. Self-esteem was measured with the Rosenberg's Self-Esteem Scale.

RESULTS

Self-esteem is significantly associated with IA. For every unit increase in self-esteem, the chance of having IA decreased by 11%. By comparison, comorbidities such as substance-use disorder (excluding tobacco), mood disorder, and eating disorder were significantly more likely among Internet-addicted than in the non-addicted group. This could not be reported for anxiety disorders. A logistic regression showed that by adding self-esteem and psychopathology into the same model, self-esteem maintains its strong influence on IA.

DISCUSSION AND CONCLUSIONS

Self-esteem was associated with IA, even after adjustment for substance-use disorders, mood disorder, and eating disorder. Self-esteem and psychopathology should be considered in prevention, intervention measures, as well as in the conception of etiological models.

The Prevalence and Psychosocial Correlates of Internet Gaming Disorder

BACKGROUND

Internet gaming disorder (IGD) is the problematic use of computer games (whether online or offline) Its prevalence throughout Germany among children, adolescents, and young adults has not yet been estimated.

METHODS

A representative sample of 1531 12- to 25-yearolds in Germany was studied in September 2016 with a standardized instrument (Internet Gaming Disorder Scale, IGDS). Sociodemographic and psychosocial data about the participants were also obtained. Prevalence estimates and binary logistic regressions were calculated (both with and without multiple imputations in the IGDS).

RESULTS

The estimated prevalence of IGD among 12- to 25-year-olds in Germany is 5.7% (95% confidence interval: [4.5; 6.9]). In a sensitivity analysis taking multiple imputations into account, this value rose to 7.0% [5.8; 8.5]. The estimated prevalence was higher in males than in females: 8.4% [6.4; 10.4] versus 2.9% [1.7; 4.1], p<0.001. Statistically significant associations with IGD were seen for male sex, lower age, higher depressiveness, higher anxiety, and more frequent neglect of social contacts due to computer games.

CONCLUSION

In view of the IGD prevalence estimates obtained in this study, further research on this disorder, its correlates, and its etiology is warranted, particularly longitudinal studies. Young persons with the psychosocial features mentioned above should be specifically asked about their use of computer games.

Problematic Gaming and Internet Use but Not Gambling May Be Overrepresented in Sexual Minorities - A Pilot Population Web Survey Study

Background: Substance-related addictive disorders are known to be overrepresented in non-heterosexual individuals, but it is largely unknown whether this is also the case for behavioral addictions such as problem gaming and gambling. This study aimed, in a pilot web survey design, to assess whether problematic gambling, gaming and internet use may be more common in individuals with a non-heterosexual orientation. Methods: An online survey was distributed through media and social media, and answered by 605 individuals (51% women and 11% non-heterosexual). Problem gambling, problem gaming and problematic internet use were measured through structured screening instruments (the CLiP, the GAS and the PRIUSS, respectively). Results: Problem gaming and problematic internet use were significantly more prevalent in non-heterosexual subjects. Instead, problem gambling did not differ between heterosexual and non-heterosexual respondents. Psychological distress and social media use for more than 3 h daily were significantly more common in non-heterosexual respondents. In the overall sample, gaming and gambling were associated statistically. Conclusion: Based on the present pilot online survey, problematic gaming and internet use, but not problem gambling, may be more common in non-heterosexual populations. This area merits more and larger studies, and potentially preventive efforts aimed for non-heterosexual individuals in the population. Possible explanations and study limitations are discussed in the paper.

Cognitive-behavioral therapy for Internet gaming disorder: A systematic review and meta-analysis

OBJECTIVE

Although there is sufficient research and clinical evidence to support the inclusion of gaming disorder in the latest revision of the International Classification of Diseases, relatively little is known about the effectiveness of first-line psychological treatment for gaming disorder or internet gaming disorder (IGD) as it is listed in the Diagnostic and Statistical Manual. This systematic review employed meta-analytic techniques to determine the effectiveness of cognitive-behavioural therapy (CBT) for IGD on four key outcomes: IGD symptoms, anxiety, depression, and time spent gaming.

METHOD

A database search identified 12 independent CBT studies. Effect size estimates (Hedges' g) with associated confidence intervals, prediction intervals, and p values for each pre-post treatment outcome, were calculated. Study reporting quality was evaluated in accordance with the Consolidated Standards of Reporting Trials guidelines. Subgroup and moderator analyses were undertaken to investigate potential sources of heterogeneity.

RESULTS

CBT demonstrated high efficacy in reducing IGD symptoms (g = 0.92; [0.50, 1.34]) and depression (g = 0.80, [0.21, 1.38]), and showed moderate efficacy in reducing anxiety (g = 0.55, [0.17, 0.93]) at post-test. There was insufficient power to determine whether CBT was capable of reducing time spent gaming. Treatment gains at follow-up were nonsignificant across the four treatment outcomes.

CONCLUSIONS

The pooled findings suggest that CBT for IGD is an effective short-term intervention for reducing IGD and depressive symptoms. However, the effectiveness of CBT for reducing actual time spent gaming was unclear. Given the limitations of this evidence base, there is a need for more rigorous studies to determine the potential long-term benefits of CBT for IGD.

PUBLIC HEALTH SIGNIFICANCE STATEMENT

Given the rise in treatment demand for internet gaming disorder (IGD) and problematic gaming, it is necessary to determine which treatments are most effective for whom and under which conditions. This review shows that cognitive-behavioural therapy for IGD, which is often considered the first-line therapy, can improve IGD symptoms and comorbid depression. However, treatment gains tend to be short-term and their effect in reducing time spent gaming is unclear. Programs that target problematic gaming may be improved by additional support beyond the standard program of therapy sessions. More funding and resources are needed to support the development of a more rigorous evidence base on IGD and its treatment.

Internet gaming disorder: Feeling the flow of social games

Introduction

Gaming Disorder (GD) was added to the recent publication of the International Classification of Diseases (ICD-11) by the World Health Organization. This aligns with recommendations of the fifth edition of the Diagnostic Statistical Manual for Mental Disorders (DSM-5), issued by the American Psychiatric Association. Accordingly, further relevant research has been invited. The interplay between preference for online social game genres, the degree of online Flow (or immersive pleasure) experienced, and the gamer's biological gender were examined here as contributing factors of IGD.

Method

A normative sample of adult internet gamers was collected online (N = 237, Age = 18-59, Males = 157; 66%; Females = 80; 34%). Participants completed the nine-item Internet Gaming Disorder Scale-Short Form (IGDS-SF9), the Online Flow Questionnaire (OFQ), and also self-reported demographics and internet/gaming behaviours.

Results

Mediation and moderated mediation analyses indicated that the level of online Flow experienced considerably mediated the association between the preference for social games genres and the intensity of IGD behaviours across both biological genders.

Conclusions

Results suggest that the level of online Flow experienced constitutes a risk factor in relation to the development of IGD. Furthermore, games which mandate social interaction with others present to be conducive to online Flow, and thus enhancing IGD risk irrespective of the biological gender of the gamer. Implications and limitations of the study are discussed.

Problematic Gaming Behavior Among Finnish Junior High School Students: Relation to Socio-Demographics and Gaming Behavior Characteristics

Multiplatform digital media use and gaming have been increased in recent years. The aim of this study was to examine associations between sociodemographics and digital gaming behavior characteristics (i.e., gaming time, medium, and genres) with problematic gaming behavior in adolescents. A convenience sample of Finnish junior high school students (n = 560; mean age 14 years, ranging from 12 to 16 years) participated in the cross-sectional survey, of which, 83% (n = 465) reported having played digital games regularly. Sociodemographic data, different forms of digital media use, gaming behavior characteristics and problematic gaming behavior was assessed. Study participants spent on average one hour per day playing digital games; casual games (23.9%), shooting games (19.8%), and sport games (12.9%), were the most popular games among participants. By using regression analysis, a blended family structure and gaming time related positively to problematic gaming behavior. Preferences for game genres such as solo, Massively Multiplayer Online Role-Playing and strategy-management games were also positively associated with problematic use of digital games. These findings provide knowledge that can be utilized in the prevention of the possible negative consequences of digital gaming.

Chinese adaptation of the Ten-Item Internet Gaming Disorder Test and prevalence estimate of Internet gaming disorder among adolescents in Taiwan

BACKGROUND AND AIMS

Internet gaming disorder (IGD) is an increasingly important topic and has been included in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) research criteria. This study aims to validate the Chinese version of the Ten-Item Internet Gaming Disorder Test (IGDT-10), a self-reported questionnaire based on DSM-5 IGD criteria, and to estimate the prevalence of IGD in adolescents.

METHODS

The IGDT-10 was translated to Chinese as a 10-item questionnaire rated on a 3-point Likert scale to evaluate the symptoms of IGD. Overall, 8,110 students from grade four to senior high who played Internet games were administered the questionnaire. In addition, 76 senior high-school students were interviewed using DSM-5 criteria to determine the optimal cut-off point that ensures adequate sensitivity, specificity, and diagnostic accuracy. The cut-off point was determined using the Youden's index and optimal diagnostic accuracy.

RESULTS

The Chinese version of the IGDT-10 showed good internal consistency (Cronbach's α = .85) and adequate diagnostic efficiency (area under the curve = 0.810). Through interviews, the optimal cut-off point was determined to be five out of the nine criteria (Youden's index: 42.1%, diagnostic accuracy: 86.8%, sensitivity: 43.8%, and specificity: 98.3%). In this study, the prevalence of IGD among adolescent gamers was 3.1%.

CONCLUSION

Findings evidence the validity and diagnostic accuracy of the IGDT-10 in the assessment of IGD.

Policy and prevention efforts for gaming should consider a broad perspective

Internet gaming disorder is gaining attention around the world. Some efforts have been directed toward preventing gaming problems from developing or persisting, but few approaches have been empirically evaluated. No known effective prevention intervention exists. Reviewing the broader field of prevention research should help research and best practices move forward in abating problems that arise from excessive gaming.

Game Addiction Scale Assessment Through a Nationally Representative Sample of Young Adult Men: Item Response Theory Graded-Response Modeling

BACKGROUND

The 7-item Game Addiction Scale (GAS) has been validated under standard confirmatory factor analysis and exhibits good psychometric properties. Whether this scale satisfies the necessary conditions for consideration by item response theory (IRT) modeling remains unknown. However, the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) recently proposed criteria, in its section 3, to define internet gaming disorder (IGD) to promote research on this possible condition.

OBJECTIVE

The objective of our study was to (1) analyze GAS in the context of IRT (graded-response) modeling; (2) investigate differential item functioning (DIF), a feature of IRT modeling, in 2 subsamples; and (3) contribute to the ongoing (IGD) debate related to the validity of the DSM-5 criteria using GAS items as a proxy.

METHODS

We assessed 2 large representative samples of Swiss men (3320 French-speaking and 2670 German-speaking) with GAS.

RESULTS

All items comprised high discrimination parameters. GAS items such as relapse, conflict, withdrawal, and problems (loss of interests) were endorsed more frequently in more severe IGD stages, whereas items related to tolerance, salience (preoccupation), and mood modification (escape) were endorsed more widely among participants (including in less severe IGD stages). Several DIF effects were found but were classified as negligible.

CONCLUSIONS

The results of the analyses partly support the relevance of using IRT to further establish the psychometric properties of the GAS items. This study contributes to testing the validity of the IGD criteria, although cautious generalization of our findings is required with GAS being only a proxy of the IGD criteria.

Prevalence of internet gaming disorder in adolescents: A meta-analysis across three decades

The inclusion of "Internet gaming disorder (IGD)" in the fifth edition of Diagnostic and statistical manual of mental disorders (DSM-5) creates a possible line of research. Despite the fact that adolescents are vulnerable to IGD, studies had reported wide array of prevalence estimates in this population. The aim of this paper is to review the published studies on prevalence of IGD among adolescents. Relevant studies prior to March 2017 were identified through databases. A total of 16 studies met the inclusion criteria. The pooled prevalence of IGD among adolescents was 4.6% (95% CI = 3.4%-6.0%). Male adolescents generally reported higher prevalence rate (6.8%, 95% CI = 4.3%-9.7%) than female adolescents (1.3%, 95% CI = 0.6%-2.2%). Subgroup analyses revealed that prevalence estimates were highest when studies were conducted in: (i) 1990s; (ii) use DSM criteria for pathological gambling; (iii) examine gaming disorder; (iv) Asia; and (v) small samples (<1,000). This study confirms the alarming prevalence of IGD among adolescents, especially among males. Given the methodological deficits in past decades (such as reliance on DSM criteria for "pathological gambling," inclusion of the word "Internet," and small sample sizes), it is critical for researchers to apply a common methodology for assess this disorder.

Personality and Cognition in Gamers: Avoidance Expectancies Mediate the Relationship Between Maladaptive Personality Traits and Symptoms of Internet-Gaming Disorder

Internet-gaming disorder (IGD) has become a clinically relevant phenomenon worth investigating with respect to its mechanisms of development and maintenance. Considering theoretical models of specific Internet-use disorders, we assumed an interaction of maladaptive personality traits as unspecific predisposing factors and experience-based, gaming-related Internet-use expectancies in predicting symptoms of IGD. Therefore, 103 male and female regular Internet gamers were investigated with questionnaires assessing maladaptive personality traits in accordance to DSM-5, gaming-related positive and avoidance Internet-use expectancies, and symptoms of IGD. The results demonstrated that negative affectivity, detachment, antagonism, disinhibition, psychoticism as well as gaming-related positive and avoidance expectancies were related to symptoms of IGD. Moreover, the relationship between maladaptive personality traits as represented by negative affectivity, detachment, and psychoticism with symptoms of IGD was mediated by avoidance expectancies. Positive gaming-related use expectancies were related to detachment, and were not a significant mediator in the hypothesized model. The findings give reason to assume that maladaptive personality traits in combination with gaming-related positive expectancies and avoidance expectancies are important factors for the development of IGD, but that positive expectancies and avoidance expectancies play a differential role regarding there mediating role between personality characteristics and symptoms of IGD.

Discordance between self-report and clinical diagnosis of Internet gaming disorder in adolescents

This study aimed to estimate overreporting (the false positive) and underreporting (false negative) rates in self-reported IGD assessment compared with clinical diagnosed IGD. The study population consisted of 45 with IGD and 228 without IGD based on clinical diagnosis from the Internet User Cohort for Unbiased Recognition of Gaming Disorder in Early Adolescence (iCURE) study. All participants completed self-reported IGD assessments. Clinical interviews were conducted blindly by trained mental health professionals based on DSM-5 IGD criteria. Self-assessed average daily amount of gaming time and game genre were measured. Psychological characteristics, including anxiety, suicidality, aggression, self-control, self-esteem, and family support, were obtained from the baseline survey. The false-negative rate for self-reported IGD assessment was 44%. The false-negative group reported less time playing online games than the IGD group, though their psychological characteristics were similar to those of the IGD group. The false-positive rate was 9.6%. They reported more time playing online games than non-IGD group, though their psychological characteristics were similar to those of non-IGD group except self-control. The discrepancy of IGD diagnoses between self-reports and clinical diagnosis revealed limitations of self-measurements. Various strategies are required to overcome the methodological shortfalls of self-reports for the assessment of IGD.

Internet gaming disorder in children and adolescents: a systematic review

AIM

Internet gaming disorder (IGD) is a serious disorder leading to and maintaining pertinent personal and social impairment. IGD has to be considered in view of heterogeneous and incomplete concepts. We therefore reviewed the scientific literature on IGD to provide an overview focusing on definitions, symptoms, prevalence, and aetiology.

METHOD

We systematically reviewed the databases ERIC, PsyARTICLES, PsycINFO, PSYNDEX, and PubMed for the period January 1991 to August 2016, and additionally identified secondary references.

RESULTS

The proposed definition in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition provides a good starting point for diagnosing IGD but entails some disadvantages. Developing IGD requires several interacting internal factors such as deficient self, mood and reward regulation, problems of decision-making, and external factors such as deficient family background and social skills. In addition, specific game-related factors may promote IGD. Summarizing aetiological knowledge, we suggest an integrated model of IGD elucidating the interplay of internal and external factors.

INTERPRETATION

So far, the concept of IGD and the pathways leading to it are not entirely clear. In particular, long-term follow-up studies are missing. IGD should be understood as an endangering disorder with a complex psychosocial background.

WHAT THIS PAPER ADDS

In representative samples of children and adolescents, on average, 2% are affected by Internet gaming disorder (IGD). The mean prevalences (overall, clinical samples included) reach 5.5%. Definitions are heterogeneous and the relationship with substance-related addictions is inconsistent. Many aetiological factors are related to the development and maintenance of IGD. This review presents an integrated model of IGD, delineating the interplay of these factors.

Passion or addiction? Correlates of healthy versus problematic use of videogames in a sample of French-speaking regular players

A criticism of current diagnostic approaches to gaming disorder is that they fail to take into account that high and repeated engagement is not problematic per se, nor is it necessarily associated with adverse consequences. To tackle this controversy, we used Confirmatory Factor Analysis (CFA) to test, in regular gamers (N = 268), whether high (but healthy) engagement can be distinguished from problematic engagement by using the Addiction-Engagement Questionnaire (Charlton & Danforth, 2007). We then tested whether differential relationships exist between the engagement and addiction constructs, DSM-5 criteria for Internet gaming disorder (IGD), and psychological factors linked to gaming use and misuse (self-reported impulsivity, motives to play, and depression). Results indicated that a model holding engagement and addiction as two distinct, but related, constructs fits the data well. Second, we showed that although both constructs are linked to the number of IGD criteria endorsed, the relationship is more pronounced for the addiction construct. Third, a differential pattern of correlations was observed with the other study variables, further supporting the need to distinguish the two constructs. Our study emphasizes that research is needed to refine the diagnostic approach to gaming disorder to avoid conflating healthy passion with pathological behavior.

Psychometric validation of the Turkish nine-item Internet Gaming Disorder Scale-Short Form (IGDS9-SF)

The main aims of the current study were to test the factor structure, reliability and validity of the nine-item Internet Gaming Disorder Scale-Short Form (IGDS9-SF), a standardized measure to assess symptoms and prevalence of Internet Gaming Disorder (IGD). In the present study participants were assessed with the IGDS9-SF, nine-item Internet Gaming Disorder Scale (IGDS) and the Young's Internet Addiction Test-Short Form (YIAT-SF). Confirmatory factor analyzes demonstrated that the factor structure (i.e., the dimensional structure) of the IGDS9-SF was satisfactory. The scale was also reliable (i.e., internally consistent with a Cronbach's alpha of 0.89) and showed adequate convergent and criterion-related validity, as indicated by statistically significant positive correlations between average time daily spent playing games during last year, IGDS and YIAT-SF scores. By applying the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) threshold for diagnosing IGD (e.g., endorsing at least five criteria), it was found that the prevalence of disordered gamers ranged from 0.96% (whole sample) to 2.57% (e-sports players). These findings support the Turkish version of the IGDS9-SF as a valid and reliable tool for determining the extent of IGD-related problems among young adults and for the purposes of early IGD diagnosis in clinical settings and similar research.

Psychometric assessment of the Internet Gaming Disorder diagnostic criteria: An Item Response Theory study

Internet Gaming Disorder (IGD) has been recognized by the American Psychiatric Association (APA) as a tentative disorder in the latest fifth revision of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5). In order to advance research on IGD, the APA has suggested that further research on the nine IGD criteria to investigate its clinical and empirical feasibility is necessary. The aim of the present study was to develop the Polish the Internet Gaming Disorder Scale–Short-Form (IGDS9-SF) and scrutinize the nine IGD criteria empirically. To achieve this, the newly developed IGDS9-SF was examined using a wide range of psychometric methods, including a polytomous Item Response Theory (IRT) analysis to evaluate the measurement performance of the nine IGD criteria. A sample of 3377 gamers (82.7% male, mean age 20 years, SD = 4.3 years) was recruited online for the present study. Overall, the findings obtained confirmed that suitability of the Polish IGDS9-SF to assess IGD amongst Polish gamers given the adequate levels of validity and reliability found. The IRT analysis revealed that the IGDS9-SF is a suitable tool to measure IGD levels above the average; however, criteria “continuation” (item 6), “deception” (item 7), and “escape” (item 8) presented with poor fit. Taken together, these results suggest that some of the diagnostic criteria may present with a different clinical weighting towards final diagnosis of IGD. The implications of these findings are further discussed.

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The APA diagnostic criteria for IGD was investigated in a large sample of gamers.

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The construct of IGD was examined via validity analysis and Item Response Theory.

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The results revealed the suitability of the IGDS9-SF to assess IGD-related symptoms.

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Each IGD criterion present with distinct clinical diagnostic weighting.

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The nine IGD criteria need to take into account different clinical weighting.

Cortical thickness and volume abnormalities in Internet gaming disorder: Evidence from comparison of recreational Internet game users

Although online gaming may lead to Internet gaming disorder (IGD), most players are recreational game users (RGUs) who do not develop IGD. Thus far, little is known about brain structural abnormalities in IGD subjects relative to RGUs. The inclusion of RGUs as a control group could minimize the potential effects of gaming experience and gaming-related cue familiarity on the neural mechanism of IGD subjects. In this study, structural magnetic resonance imaging data were acquired from 38 IGD subjects and 66 RGUs with comparable age, gender, and educational level. Group differences in cortical thickness and volume were analyzed using the FreeSurfer software. Correlations between cortical changes and addiction severity were calculated for both groups. Compared with the RGU group, the IGD group showed significantly decreased cortical thickness in the left lateral orbitofrontal cortex, inferior parietal lobule, bilateral cuneus, precentral gyrus, and right middle temporal gyrus. Moreover, significantly reduced cortical volume was observed in the left superior temporal gyrus and right supramarginal gyrus in the IGD group. Whole-brain correlational analysis indicated different correlations between the two groups. The brain regions that showed group differences were considered to be involved in cognitive control, decision making, and reward/loss processing. These functions may serve as potential mechanisms that explain why IGD individuals experience negative outcomes in frequent game playing.