Massively multiplayer online role-playing games (MMORPG): Association between its addiction,self-control and mental disorders among young people in Vietnam

Abstract

Aims:

To explore the association between MMORPG addiction and mental health status, and between self-control ability and mental health status among young male MMORPG players in Hanoi, Vietnam.

Methods:

In this cross-sectional study, 10 computer game rooms were randomly selected out of 77 in five communes in Hanoi. From these game rooms, 350 MMORPG players were purposively recruited as a study group, of whom 344 completed the questionnaire. In the same five communes, 344 non-players were selected as a control group. An online game addiction scale, a self-control scale and the Vietnamese SRQ-20 were used to measure the degree of MMORPG addiction, self-control ability and level of mental disorders.

Results:

MMORPG players had significantly higher mental disorders scale scores than non-players (p < .001). The strongest positive correlation was detected between MMORPG addiction scale scores and mental disorders scale scores (r = 0.730, p < .001). Self-control scale scores were negatively associated with mental disorders scale scores (r = -0.345, p < .001). The average amount of money spent on games per month, MMORPG addiction scale score and self-control scale score were considered the best predictors of a higher mental disorders scale score.

Conclusion:

Young, male MMORPG players with higher addiction scores were more likely to have higher mental disorders scale scores, and such mental status was negatively associated with the level of self-control in Hanoi, Vietnam. Closer attention should be paid to prevent mental disorders among MMORPG players.

Keywords

Massively multiplayer online role-playing games MMORPG addiction self-control mental disorders Vietnam

Introduction

Massively multiplayer online role-playing games (MMORPG) is the latest genre of internet-only computer games that has come to be viewed as a serious social problem in many countries (Peters & Malesky, 2008; Smyth, 2007; Zhou & Li, 2009). When players play MMORPG, they can assume any role they desire in virtual communities and collaborate with each other to accomplish missions of a fairly aggressive nature, such as arson, killing and robbery. Such entertaining, interactive and real-time online games have become ‘killer applications’ on the internet.

In 2007 there were an estimated 12.5 million MMORPG subscribers worldwide (Meenan, 2007). The phenomenon of ‘online game addiction’ has spread widely in recent years (Ng & Wiemer-Hastings, 2005). In a recent study, one in five adolescents was found to be currently ‘dependent’ upon computer games (Smahel, Blinka, & Ledabyl, 2008). In another study, about 40% of respondents considered themselves addicted (Griffiths, Davies, & Chappell, 2004). Younger players are generally more prone to addiction (Smahel et al., 2008). Aggression and narcissistic personality traits were positively correlated with online game addiction, whereas self-control was negatively correlated with online game addiction (Kim, Namkoong, Ku, & Kim, 2008).

MMORPG players tend to spend a substantial amount of time playing the games (Griffiths et al., 2004). In a recent study of players who came from 21 different countries, some reported playing over 70 hours per week. Over 60% of players mentioned that they sometimes spent over 10 hours at a time playing the game. Sometimes players must band together into guilds to go on a quest or raid that can require 10 or more hours of continuous play (Griffiths et al., 2004).

A relationship between the excessive use of online games and mental disorders has been reported (Plusquellec, 2000). Also, as the amount of time spent playing online games increases, the quality of players’ interpersonal relationships decreases and their social anxiety increases (Lo, Wang, & Fang, 2005). Also, a significant negative relationship has been revealed between online game-playing frequency and life satisfaction in adolescents (Wang, Chen, Lin, & Wang, 2008).

According to the World Health Organization (WHO, 2002, 2005), mental disorders are the single most common cause of disability in young people. The onset of 70% of mental disorders occurs prior to the age of 25 (Kessler et al., 2005). The prevalence of psychiatric disorders has been found to range from 12% to 29% among children visiting primary care facilities in various countries. Primary health care workers recognized only 10%–22% of these cases, and the vast majority of children did not receive appropriate mental health services (Giel et al., 1981). If left untreated, mental disorders can impede all aspects of health, including emotional well-being and social development. They leave young people feeling socially isolated, stigmatized and unable to optimize their social, vocational and interpersonal contributions to society (McKewan, Waddell, & Barker, 2007).

However, the mental health care of children and adolescents has not been well studied in Vietnam to date (Goren, 2007). Mental health services for children in Vietnam are particularly limited due to the prioritization of other health problems, such as infectious diseases and malnutrition (Goren, 2007). The current role of child psychiatry in Vietnam is still limited because the health care system focuses more on children’s malnutrition and disability (Kim et al., 2008).

Although an association between depression and internet addiction among adolescents and adults has been reported (Kim et al., 2006), most studies of mental health and internet use have not examined MMORPG specifically. Until recently, studies related to MMORPG have mainly concentrated on the demographics of play and predictive factors for addiction. For example, a recent study that investigated psychological predictors of problematic involvement in MMORPG revealed that problematic use of MMORPG is significantly predicted by high urgency and a motivation to play for immersion (Billieux et al., 2011). One of the few qualitative studies on MMORPG showed how gamers used MMORPG to alleviate negative feelings and how different personal problems arise from playing the games (Hussain & Griffiths, 2009). Another recent study demonstrated that those who spent more time with MMORPG presented lower levels of offline social support and higher levels of negative psychological symptoms (Longman, O’Connor, & Obst, 2009). Nevertheless, little research has been done on characteristics of MMORPG gamers and their addiction level (Achab et al., 2011). Also, much of what we know about MMORPG and mental health in Vietnam comes from case reports from mental health treatment settings.

The main aim of this study, therefore, was to explore (1) the association between MMORPG addiction and mental health status, and (2) the association between self-control ability and mental health status, among young male MMORPG players in Hanoi, Vietnam. We hypothesized that higher levels of MMORPG addiction would be associated with higher levels of mental disorders and that better self-control ability would be associated with lower levels of mental disorders. This study contributes to the literature by adding information about the characteristics of MMORPG gamers and the association between their addiction and psychological status among youths in Vietnam, where limited research has been done.

Methods

Study site

This cross-sectional study was conducted in five communes in Hanoi, Vietnam, which were selected by random sampling. For this, we randomly selected five districts from the list of all 29 Hanoi districts. We then randomly selected one out of eight to 29 communes in each district. Selected communes were Ngoc Khanh (Ba Dinh district), Lang Ha (Dong Da district), Tan Mai (Hoang Mai district), Thuy Khue (Tay Ho district) and Lien Bat (Ung Hoa district). Out of the five communes, four, namely Ngoc Khanh, Lang Ha, Tan Mai and Thuy Khue, are located in the central part of Hanoi, whereas Lien Bat is located in the suburbs of Hanoi. Out of the 77 computer game rooms in the five communes, 10 were randomly selected from lists obtained from local governments. Each game room had more than 12 computers and was open from 6.00 am to 11.00 pm.

Study participants

Study participants consisted of 344 MMORPG players as a study group and 344 non-players as a control group. MMORPG players were recruited using a convenience sampling method at the 10 computer game rooms. Inclusion criteria for MMORPG players were as follows: male, aged from 10 to 24 years, and having at least one month of experience in MMORPG playing. In this study, we selected only males because previous studies showed that men played more regularly than women and were more likely to be dependent on the games (Griffiths & Hunt, 1998). We found an appropriate control group of non-players after selecting MMORPG players. Non-players were selected from the list of residents in the same communes. We matched one to one their gender, age, education and occupation with MMORPG players.

Questionnaire and measurement scales

Socio-demographic data

We obtained the following socio-demographic and MMORPG-related general data from the respondents: age, level of education, occupation, kinds of MMORPG being played most frequently, reasons for playing, average amount of time spent on games per week (hours), average amount of money spent on games per month (Vietnam dong) and MMORPG playing experience (months).

Online game addiction scale

An online game addiction scale was used to measure the degree of MMORPG addiction (Whang & Chang, 2002). The online game addiction scale has 20 items related to online game use, including time spent on online games, psychological dependence, compulsive use, withdrawal, as well as problems with school activities, work, sleep and family relationships. For each item, a graded response was selected from the following options: 1= not at all; 2 = occasionally; 3 = frequently; 4 = often; 5 = always. The range of possible total scores was 20–100, a higher score implying a tendency towards addictive usage (Kim et al., 2008).

The English version of the online game addiction scale was translated into Vietnamese. A Vietnamese Bachelor who specializes in English language then back-translated the scale into English and the original questions were identified adequately. In this study, the translated version was found to have high internal reliability as assessed by Cronbach’s α (0.95).

Self-control scale

In this study a self-control scale was also used (Arneklev, Grasmick, Tittle, & Bursik, 1993), which measures six separate aspects of self-control. The scale consists of 24 items, divided evenly into impulsivity, simple tasks, risk seeking, physical activities, self-centeredness and temper sub-components. Respondents were asked to report whether they strongly agree, agree, disagree or strongly disagree with each item. The range of possible total scores was 24–96. People with higher scores are considered to have a higher level of self-control.

The English version of the self-control scale was translated into Vietnamese and this was back-translated to English to make sure that the translation was accurate. The internal reliability of the Vietnamese scale in this study was acceptable (Cronbach’s α = 0.74).

Mental disorders scale

The level of potential mental disorders was measured by the Vietnamese Self-Reporting Questionnaire (SRQ-20) (Giang, Allebeck, Kullgren, & Tuan, 2006). The questionnaire was originally developed by the WHO as an instrument to screen for mental disorders and is applicable in different cultural settings, especially in developing countries. This instrument consists of 25 questions: 20 related to neurotic symptoms; four concerning psychosis; and one asking about convulsions (WHO, 1993). The current study used the SRQ-20, which assesses the presence of neurotic symptoms (anxiety, depression, psychosomatic). The questions are answered ‘yes’ or ‘no’ depending on the presence or absence of symptoms. The score for each question is 0 (no) or 1 (yes), with a range of possible total scores of 0–20. A higher score suggests a higher level of mental disorders. The reliability of this Vietnamese version was tested in Vietnam and was found to be satisfactory (Cronbach’s α = 0.86) (Giang et al., 2006).

Data collection

Data collection was carried out using a self-administered questionnaire in Vietnamese from 24 September to 7 October 2009. Five investigators, all students at Hanoi Medical University, were well trained for a day before going to the field for data collection.

First, we implemented a pre-test among 30 MMORPG players. Modifications were made based on the pre-test results. After modification, the questionnaire was used to collect data from 344 MMORPG players. In the control group, the same number of non-players answered only demographic information and questions related to the SRQ-20 scale. For participants under 18 years of age, data collection was carried out at their homes with the agreement of their parents.

Statistical analysis

We performed all statistical analyses using the Statistical Package for the Social Sciences (SPSS) version 17 for Windows. After calculating descriptive statistics for socio-demographic variables, a t-test was used to compare mental disorders scale scores between MMORPG players and non-players. The differences in scores of MMORPG players according to level of education, occupation, MMORPG games being played most frequently, and reasons for playing were calculated by analysis of variance (ANOVA) and a t-test. Pearson’s correlation analysis was conducted to examine the correlation coefficient (r) between mental disorders scale scores and various continuous independent variables. Finally, multiple regression analysis was carried out to investigate the best predictors of mental disorders scale scores. The level of statistical significance was set at p < .05.

Ethical issues

This research was approved by the ethical committees of the University of Tokyo and Hanoi Medical University. All participants signed informed consent forms before the interview. Their participation in this study was entirely voluntary. Any information that participants provided was strictly treated in a confidential manner; participants were not identified in the reporting of results.

Results

A total of 344 MMORPG players completed questionnaires (response rate = 98.3%) and 344 questionnaires of non-players were collected. Table 1 shows the socio-demographic and general characteristics of the participants. The mean age was 19.5 (SD = 2.7) years. Most of the participants were secondary and high school pupils (n = 116, 33.7 %) and university students (n = 176, 51.2%). Of the remaining participants, 10.5% (n = 36) were unemployed while only 4.6% (n = 16) were employed. The distribution of education levels was as follows: university of any level (n = 127, 36.9%); high school (n = 185, 53.8%); secondary school (n = 32, 9.3%).

Table 1.

Socio-demographic and general characteristics of the participants.

Variables	MMORPG players		Non-players
	n	%	n	%
Mean age in years (SD)	19.5 (2.7)		19.5 (2.7)
Level of education
Secondary school	32	9.3	32	9.3
High school	185	53.8	185	53.8
University of any level	127	36.9	127	36.9
Occupation
Pupil (secondary school and high school)	116	33.7	116	33.7
Student (university)	176	51.2	176	51.2
Employed	16	4.6	16	4.6
Unemployed	36	10.5	36	10.5

Table 2 shows the MMORPG-related characteristics of participants. The mean length of MMORPG playing experience was 36.9 (SD = 19.3) months. MMORPG games being played most frequently included Võ Lâm Truyền Kỳ (n = 102, 29.7%), Thiên Long Bát Bộ (n = 41, 11.9%), Tru Tiên (n = 32, 9.3%) and Con Đường Tơ Lụa (n = 28, 8.1%). Among the reasons for playing, the largest number of respondents chose ‘killing time’ (n = 235, 68.3%). The mean amount of time spent on MMORPG playing per week was 35.1 (SD = 30.1) hours. The average amount of money spent on the games per month was 329,646 VND (about US$18.30). The average MMORPG addiction scale score was 46.1 (SD = 18.7) and the average self-control scale score was 62.8 (SD = 6.8).

Table 2.

MMORPG-related characteristics of participants.

Variables of MMORPG players	n	%
MMORPG games being played most frequently
Võ Lâm Truyền Kỳ	102	29.7
Thiên Long Bát Bộ	41	11.9
Tru Tiên	32	9.3
Con Ðường Tơ Lụa	28	8.1
Other	141	41
Reasons for playing
Killing time	235	68.3
Levelling and building up their character	123	35.8
Earning money by selling items	83	24.1
Grouping and interacting with other people	52	15.1
Feeling superior to others	39	11.3
	M	SD
Average amount of game time (hours/week)	35.1	30.1
Average amount of money spent on games (VND/month)	329,646	356,683
Playing experience (months)	36.9	19.3
MMORPG addiction scale score	46.1	18.7
Self-control scale score	62.8	6.8

Table 3 presents a comparison of mental disorders scale scores between MMORPG players and non-players. The mean mental disorders scale score of MMORPG players was 4.8 (SD = 3.3), whereas non-players’ mean score was 1.7 (SD = 1.6). MMORPG players had a significantly higher mean mental disorders scale score than non-players (p < .001).

Table 3.

Comparison of mental disorders scale scores between MMORPG players and non-players.

	M	SD	t	p
Mental disorders scale scores			15.6	< .001***^a
MMORPG players	4.8	3.3
Non-players	1.7	1.6

Independent samples t-test

***

p < .001.

Table 4 shows the differences in mental disorders scale scores of the MMORPG-playing group according to level of education, occupation, which MMORPG game was being played most frequently, and reasons for playing, using ANOVA and a t-test. The mental disorders scale scores did not significantly differ by level of education or occupation. The scores were significantly different by kinds of MMORPG being played most frequently (p = .006). Related to reasons for playing, the scores were not significantly different for answers regarding ‘levelling and building up their character’, ‘grouping and interacting with other people’ and ‘killing time’. However, the scores were significantly different for answers regarding ‘feeling superior to others’ (p = .004) and ‘earning money by selling items’ (p < .001).

Table 4.

Mental disorders scale scores of MMORPG players according to level of education, occupation, MMORPG games being played most frequently, and reasons for playing.

	n	M (SD)	p
Level of education			.602^a
Secondary school	32	4.2 (3.3)
High school	185	4.8 (3.3)
University of any level	127	4.9 (3.3)
Occupation			.209^a
Pupil (secondary school and high school)	116	5.0 (3.5)
Student (university)	176	4.6 (3.1)
Employed	16	3.7 (3.2)
Unemployed	36	5.4 (3.3)
MMORPG being played most frequently			.006**^a
Võ Lâm Truyền Kỳ	102	5.3 (3.1)
Thiên Long Bát Bộ	41	5.8 (3.5)
Tru Tiên	32	5.0 (3.8)
Con Ðường Tơ Lụa	28	4.4 (2.5)
Other	141	4.1 (3.2)
Reasons for playing
Levelling and building up their character			.307^b
Yes	123	4.6 (3.2)
No	221	5.0 (3.4)
Feeling superior to others			.004**^b
Yes	39	4.6 (3.2)
No	305	6.2 (3.4)
Grouping and interacting with other people			.134^b
Yes	52	4.7 (3.3)
No	292	5.4 (3.0)
Earning money by selling items			< .001***^b
Yes	83	4.1 (3.0)
No	261	6.7 (3.2)
Killing time			.851^b
Yes	235	4.8 (3.2)
No	109	4.7 (3.3)

One-way analysis of variance (ANOVA).

Independent samples t-test.

p < .01, *** p < .001.

As shown in Table 5, correlation analysis was conducted to examine the correlation coefficient (r) between mental disorders scale scores and various continuous independent variables. The strongest positive correlation, which would be considered the best predictor, was detected between MMORPG addiction scale scores and mental disorders scale scores (r = 0.730, p < .001). This means that MMORPG players who had relatively high scores on the MMORPG addiction scale were likely to have high mental disorders scale scores. Self-control scale scores were negatively related to mental disorders scale scores (r = -0.345, p < .001). Based on the above results, it was found that MMORPG addiction has a positive linear relationship with mental disorder status, where self-control has a suppressive impact on mental disorders.

Table 5.

Correlation coefficient (r) between mental disorders scale scores and various continuous independent variables.

	Mental disorders scale score (SRQ-20)
Age	-0.030
Average amount of game time per week	0.399^*
Amount of money spent on games per month	0.345^*
Playing experience	0.230^*
MMORPG addiction scale score	0.730^*
Self-control scale score	-0.345^*

p < .01 (two-tailed).

Linear multiple regression analysis was conducted by backward elimination to investigate the best predictors of mental disorders scale scores. All eight variables that were significantly correlated with the mental disorders scale scores were entered as independent variables. The results indicated that the general model was significant (F = 139.515, p < .001). Five independent variables were removed during the backward elimination process. Three variables remained in the model: average amount of money spent on games per month; MMORPG addiction scale score; and self-control scale score (Table 6). The adjusted R² squared value was 0.566. This indicates that 56.6% of the variance in mental disorders scale scores was explained by this model.

Table 6.

Multiple regression analysis to determine the amount of variance in mental disorders scale scores.

Significant variables	Linear multiple regression (adjusted R² = 0.566)^a
		SE	t	p
MMORPG addiction scale score	0.659	0.007	16.045	< .001***
Self-control scale score	-0.141	0.019	-3.642	< .001***
Amount of money spent on games per month	0.103	0.000	2.612	.009**

Insignificant variables were MMORPG games being played most frequently, feeling superior to others, earning money by selling items, average amount of game time per week, and playing experience.

p < .01, *** p < .001.

Discussion

This study identified correlates of mental disorders scale scores among young men playing MMORPG in Hanoi, Vietnam. As hypothesized, MMORPG addiction was positively correlated with mental disorders, while self-control was negatively correlated with mental disorders. MMORPG players had significantly higher mental health risk than non-players. These findings are consistent with previous research on young people that have linked the internet, online games and mental health concerns (Kim, Namkoong et al., 2008; Kim, Ryu et al., 2006; Ng & Wiemer-Hastings, 2005).

The results of this study demonstrate that our sample of MMORPG players with higher MMORPG addiction scale scores were more likely to have higher mental disorders scale scores. Similarly, a previous study has reported an association between internet addiction and depressive disorders (Kim et al., 2006). Addiction to the internet and online games has been shown to lead to consequences such as failing in school, family problems and relationship problems (Ng & Wiemer-Hastings, 2005). Another study revealed that a high dependency on online games was associated with interpersonal difficulties and stress in reality (Kim et al., 2008). By showing a high correlation coefficient (r) between mental disorders scale scores and MMORPG addiction scale scores, this study adds evidence that affirms the role of MMORPG addiction on the development of mental disorders among MMORPG players.

A higher mental disorders scale score was negatively associated with lower self-control. Self-control is involved in processes that guide and monitor behaviour (Carver & Scheier, 2000). Recent research provides support for the notion that high self-control predicts positive social interactions (Tangney, Baumeister, & Boone, 2004). Therefore, it is possible that self-control has effects on mental disorders. Another study found that internet addiction among young people was associated with their lack of self-control (Oh, 2003). Kim and colleagues (2008) also reported that self-control was negatively correlated with MMORPG addiction. Our study, as well as previous studies, indicates that low self-control may be important in the acquisition, development and maintenance of both MMORPG addiction and mental disorders among players.

The kinds of MMORPG being played most frequently and play frequency were associated with mental disorders scale scores. The four MMORPG games that were played most frequently imitate gangland lives of the past and have many scenes of violence. A recent study reported that violence in the media was related to aggressive behaviour, including seriously violent behaviour among youths (Ybarra et al., 2008). There has been great suspicion and speculation about whether the increase in player killing in the virtual world would facilitate the gamers to act violently in the real world (Whang & Chang, 2004). The average amount of time per week spent playing games in this study was 35.1 hours, which was much longer than that of adolescent gamers in a previous study in Korea (26.3 hours) (Kim et al., 2008). This finding seems to be consistent with previous studies that social anxiety increases as the amount of time spent playing online games increases (Ybarra et al., 2008). Furthermore, the prevalence of self-reported sleeping problems, depression, suicide ideations, anxiety, obsessions/compulsions and alcohol/substance abuse increases with increasing playing time (Wenzel, Chen, Lin, & Wang, 2009). The government and parents should strengthen a scheme to monitor and control the contents of MMORPG and the amount of playing time.

Multiple regression analysis revealed that the level of mental disorders among MMORPG players can be partially predicted from the combination of MMORPG addiction scale scores, self-control scale scores and the amount of money spent on MMORPG games per month. Of the socio-demographic and MMORPG-related characteristics, only the amount of money spent monthly on MMORPG remained significant related to mental disorders scale scores. Approximately 56% of the variance of mental disorders scale scores among MMORPG players was accounted for by the above three independent variables. Further study should be conducted to identify other factors that affect mental disorders among MMORPG players.

Limitations

This study has three limitations. First, we used a convenience sampling method to recruit MMORPG players. Although we made efforts to select MMORPG players at various computer game rooms in five communes of Hanoi, convenience sampling was the only choice. Second, although this study focused on the association between MMORPG addiction and mental disorders, and the association between self-control ability and mental health status, conclusions about causality could not be made because of the cross-sectional study design. Third, although SRQ-20 has been recommended as a screening instrument for mental disorders in developing countries by the WHO, it can only be used within general medical practice to rapidly identify those who might be suffering mental disorders. Clinical diagnoses were not applied to study participants and this represents a limitation for diagnosing common mental disorders.

Nevertheless, our study has a number of strengths. In this study, confounders to MMORPG players and non-players could be equal because non-players’ gender, age, education and occupation were matched with MMORPG players. This study also had a high response rate, which enabled us to recruit enough participants to ensure the statistical power to detect differences about mental disorders between the MMORPG players and non-players. Cronbach’s α for each scale was acceptable for all selected materials. The internal validity and reliability are therefore considered to be generally satisfactory.

Conclusion

In conclusion, young, male MMORPG players with higher addiction scores were more likely to have had higher mental disorders scale scores, and such mental status was negatively associated with the level of self-control in Hanoi, Vietnam. This result suggests that closer attention should be paid to prevent mental disorders among MMORPG players and it also reveals promising avenues for future research. Further prospective studies using a structured diagnostic interview are required to confirm mental disorders among MMORPG players.

Footnotes

Acknowledgements

The authors would like to thank Dr Luu Ngoc Hoat, vice-director of Hanoi Medical University, for his support of this study in Hanoi, Vietnam. We would also like to thank Mr Nguyen Quang Canh, vice-chairman of Lang Ha commune, Mr Nguyen Van Vinh, chairman of Thuy Khue commune, Mrs Tran Thi To Tam, vice-chairman of Ngoc Khanh commune, Mrs Dang Thi Thanh Binh, vice-chairman of Tan Mai commune, and Mr Cao Manh Dong, chairman of Lien Bat commune, for their support and for providing information regarding computer game rooms and residents in these communes.

References

Achab

Nicolier

Mauny

Monnin

Trojak

Vandel

… Haffen

(2011). Massively multiplayer online role-playing games: Comparing characteristics of addict vs non-addict online recruited gamers in a French adult population. BMC Psychiatry, 11, 144.

Arneklev

B. J.

Grasmick

H. G.

Tittle

C. R.

Bursik

R. J.

Jr. (1993). Low self-control and imprudent behavior. Journal of Quantitative Criminology, 9, 225–247.

Billieux

Chanal

Khazaal

Rochat

Gay

Zullino

van der Linden

(2011). Psychological predictors of problematic involvement in massively multiplayer online role-playing games: Illustration in a sample of male cybercafé players. Psychopathology, 44, 165–171.

Carver

C. S.

Scheier

M. F.

(2000). On the structure of behavioral self-regulation. In Boekaerts

Pintrich

P. R.

Zeidner

(Eds), Handbook of self-regulation (pp. 41–84). San Diego, CA: Academic Press.

Giang

K. B.

Allebeck

Kullgren

Tuan

N. V.

(2006). The Vietnamese version of the Self Reporting Questionnaire 20 (SRQ-20) in detecting mental disorders in rural Vietnam: A validation study. International Journal of Social Psychiatry, 52, 175–184.

Giel

de Arango

M. V.

Climent

C. E.

Harding

T. W.

Ibrahim

H. H.

Ladrido-Ignacio

… Younis

Y. O.

(1981). Childhood mental disorders in primary health care: Results of observations in four developing countries. A report from the WHO collaborative Study on Strategies for Extending Mental Health Care. Pediatrics, 68, 677–683.

Goren

(2007). Looking for child psychiatric nursing – Vietnam 2005. Journal of Child and Adolescent Psychiatric Nursing, 20, 156–162.

Griffiths

M. D.

Davies

M. N. O.

Chappell

(2004). Online computer gaming: A comparison of adolescent and adult gamers. Journal of Adolescence, 27, 87–96.

Griffiths

M. D.

Hunt

(1998). Dependence on computer games by adolescents. Psychological Reports, 82, 475–480.

10.

Hussain

Griffiths

M. D.

(2009). The attitudes, feelings, and experiences of online gamers: A qualitative analysis. Cyberpsychology & Behavior, 12, 747–753.

11.

Kessler

R. C.

Berglund

Demle

Jin

Merikangas

K. R.

Walters

E. E.

(2005). Lifetime prevalence and age-of-onset distributions of DSM-IV disorders in the national comorbidity survey replication. Archives of General Psychiatry, 62, 593–603.

12.

Kim

E. J.

Namkoong

Kim

S. J.

(2008). The relationship between online game addiction and aggression, self-control and narcissistic personality traits. European Psychiatry, 23, 212–218.

13.

Kim

Ryu

Chon

M. Y.

Yeun

E. J.

Choi

S. Y.

Seo

J. S.

Nam

B.-W.

(2006). Internet addiction in Korean adolescents and its relation to depression and suicidal ideation: A questionnaire survey. International Journal of Nursing Studies, 43, 185–192.

14.

S. K.

Wang

C. C.

Fang

(2005). Physical interpersonal relationships and social anxiety among online game players. Cyberpsychology, Behavior, and Social Networking, 8, 15–20.

15.

Longman

O’Connor

Obst

(2009). The effect of social support derived from World of Warcraft on negative psychological symptoms. Cyberpsychology & Behavior, 12, 563–566.

16.

McKewan

Waddell

Barker

(2007). Bringing children’s mental health ‘out of the shadows’. Canadian Medical Association Journal, 176, 471–472.

17.

Meenan

A. L.

(2007). Internet gaming: A hidden addiction. American Family Physician, 76, 1116–1117.

18.

B. D.

Wiemer-Hastings

(2005). Addiction to the internet and online gaming. Cyberpsychology, Behavior, and Social Networking, 8, 110–113.

19.

W. O.

(2003). Factors influencing internet addiction tendency among middle school students in Gyeong-buk area. Taehan Kanho Hakhoe Chi, 33, 1135–1144.

20.

Peters

C. S.

Malesky

L. A.

(2008). Problematic usage among highly-engaged players of massively multiplayer online role-playing games. Cyberpsychology, Behavior, and Social Networking, 11, 481–484.

21.

Plusquellec

(2000). Are virtual worlds a threat to the mental health of children and adolescents? Archives of Pediatric, 7, 209–210.

22.

Smahel

Blinka

Ledabyl

(2008). Playing MMORPGs: Connections between addiction and identifying with a character. Cyberpsychology, Behavior, and Social Networking, 11, 715–718.

23.

Smyth

J. M.

(2007). Beyond self-selection in video game play: An experimental examination of the consequences of massively multiplayer online role-playing game play. Cyberpsychology, Behavior, and Social Networking, 10, 717–721.

24.

Tangney

J. P.

Baumeister

R. F.

Boone

A. L.

(2004). High self-control predicts good adjustment, less pathology, better grades, and interpersonal success. Journal of Personality, 72, 271–322.

25.

Wang

E. S.

Chen

L. S.

Lin

J. Y.

Wang

M. C.

(2008). The relationship between leisure satisfaction and life satisfaction of adolescents concerning online games. Adolescence, 43, 177–184.

26.

Wenzel

H. G.

Bakken

I. J.

Johansson

Götestam

K. G.

Øren

(2009). Excessive computer game playing among Norwegian adults: Self-reported consequences of playing and association with mental health problems. Psychological Reports, 105, 1237–1247.

27.

Whang

L. S.

Chang

(2002). Psychological analysis of online game users. Proceedings of Human–Computer Interaction, 2, 81–90.

28.

Whang

L. S.

Chang

(2004). Lifestyles of virtual world residents: Living in the online game ‘lineage’. Cyberpsychology, Behavior, and Social Networking, 7, 592–600.

29.

WHO (World Health Organization). (1993). A user’s guide to self-reporting questionnaire. Geneva: WHO.

30.

WHO. (2002). The world health report 2001: Mental health – new understanding, new hope. Geneva: Bookwell Publications.

31.

WHO. (2005). Child and adolescent mental health policies and plans (mental health policy and service guidance package). Geneva: WHO.

32.

Ybarra

M. L.

Diener-West

Markow

Leaf

P. J.

Hamburger

Boxer

(2008). Linkages between internet and other media violence with seriously violent behavior by youth. Pediatrics, 122, 929–937.

33.

Zhou

(2009). Online game addiction among Chinese college students measurement and attribution. Studies in Health Technology and Informatics, 144, 149–154.