Health effects of video and computer game playing

Many children and young people play TV- or computer games on a regularly basis. To get a picture of the effects of playing those games, the Swedish National Institute of Public Health has performed a systematic review of available scientific studies on the issue. This systematic review shows that there is limited evidence for playing violent video and computer games causing children to choose aggressive toys. Available research does not provide any support for a link between video game playing and aggressive feelings, aggressive thoughts or aggressive behaviours – despite all these outcomes having been well studied. Moreover, the available longitudinal studies of video game playing and overweight do not support a link. At the same time, there is a strong support for video and computer game playing giving positive effects on cognitive abilities.

Health effects of video and computer game playing A systematic review Anton Lager and Sven Bremberg

National Institute of Public Health Distribution SE-120 88 Stockholm

Fax +46 8 449 88 11 E-mail [email protected] Internet www.fhi.se

swedish national institute of public health

www.fhi.se


© Swedish National Institute of Public Health isbn: 978-91-7257-519-6 Stockholm (Translation of Swedish NIPH Report 2005:18, ISSN: 1651-8624, ISBN: 91-7257-348-1) Authors: Anton Lager and Sven Bremberg.

Contents

Abstract ........................................................................................................................... 3 Background and aim....................................................................................................... 4 Method............................................................................................................................ 5 Study designs .............................................................................................................. 5 Search strategy ............................................................................................................ 6 Selection criteria ......................................................................................................... 6 Data collection and analysis ....................................................................................... 7 Results............................................................................................................................. 9 Spatial abilities and reaction time ............................................................................ 10 Aggressive play........................................................................................................... 11 Aggressive feelings, thoughts and behaviours........................................................... 11 Overweight .................................................................................................................12 Discussion ......................................................................................................................13 Comparison with other reviews .................................................................................14 Authors...........................................................................................................................15 References......................................................................................................................16 Appendix........................................................................................................................21

Abstract

Background: A large proportion of children and young people play video or computer games regularly. The aim of this study was to clarify the health effects of playing through a systematic review of scientific studies. Method: The analysis was limited to randomised controlled trials, controlled experiments and prospective longitudinal studies. The literature searches were conducted without pre-defined health outcomes. Eight databases were searched. Results: 30 studies were identified, 26 of them experiments and 4 prospective longitudinal studies. The following six outcomes were studied in at least three experiments: spatial abilities, reaction time, aggressive play, aggressive thoughts/interpretations, aggressive feelings, and aggressive behaviour. The studies of spatial abilities and reaction time were of high quality and consistently showed positive effects. The studies of aggression varied in quality. Effects were only shown in studies that did not meet all quality criteria. One effect was shown in two studies that partly met the criteria: increased choice of aggressive toys. One outcome – overweight – was studied in two prospective longitudinal studies but no clear effects were shown. Discussion: The review provides strong evidence for video and computer game playing having positive effects on spatial abilities and reaction time. Spatial ability is considered to be one of the most important parts of intelligence. The studies give limited support for playing of violent games causing children to choose aggressive toys, but it is unclear how this is to be best interpreted since the studies provide no evidence for a link between video and computer game playing and aggressive feelings, thoughts or behaviours despite these outcomes having been well studied. The two longitudinal studies of video and computer game playing and overweight do not support a link.

-3HEALTH EFFECTS OF VIDEO AND COMPUTER GAME PLAYING

Background and aim

A large proportion of children and young people regularly play video or computer games. In a study of 3-8 year-olds in 1998-1999, 66 per cent of boys and 52 per cent of girls used a computer for playing games every week (1). Video and computer game playing seems to be just as common among older boys, see Figure 1. Playing among girls diminishes up to the age of 16-17 but is still a regular activity among nearly half of the girls aged 10-12 years.

80 70

Percent

60 50 40 30 20 10 0 10-12 years old

16-17 years old Girls

Boys

Figure 1. Proportion of Swedish children who play video or computer games several times a week, 2000-01. Source: Upp till 18, 2004 (2).

It is motivated to reflect on the health effects of video and computer game playing. In examining this, it is an advantage to rely on studies rather than theories and ideas regarding what are appropriate behaviours for children. The aim of this review was therefore to clarify the health effects of video and computer game playing through a systematic review of scientific studies. The concept of health was used in a broad sense, that is including mental, physical and social aspects.


Method

Study designs Some aspects of video and computer game playing can be observed in experiments, that is, studies in which researchers are actively involved and change one or more factors to examine the effects (3). The most reliable experiments are designed as randomised controlled trials (RCT) in which participants are distributed randomly into experimental and control groups. A pre-measurement of both groups is conducted. The experimental group is subjected to the exposure, the effects of which the researchers wish to measure, e.g. computer game playing. In other respects, the experimental and control groups are treated in exactly the same way. If the groups differ after the experiment in a way that they did not do before the trial started, it is likely that the differences are due to the exposure. Some studies do not fulfil the criteria for randomisation or pre-measurement. The reliability of such studies is lower. In experiments completely without control groups, the possibility that the changes among participants are due to factors other than the exposure can not be ruled out at all Experiments of this kind are not sufficiently reliable as a basis for conclusions regarding causal links. Certain aspects of video and computer game playing cannot be studied in experiments. The scientific basis in this case instead consists of cross-sectional or longitudinal studies. A cross-sectional study examines simultaneous occurrence of a phenomenon, such as aggression, with the incidence of the factor believed to cause the phenomenon, such as video or computer game playing. It is generally not possible to make conclusions about causes on the basis of such studies. In longitudinal studies there is some degree of control over the direction of the causal link since exposure precedes the outcome in time. The reliability of these studies increases if they are prospective, i.e. performed so that exposure is examined at one point in time and the outcome at a later point in time. There is a risk that a third unknown factor - a confounder - can explain both the exposure and the outcome -5HEALTH EFFECTS OF VIDEO AND COMPUTER GAME PLAYING

respectively. To ensure adequate reliability, the study must control for possible confounders. For the reasons discussed, this review was limited to randomised controlled trials, controlled experiments and prospective longitudinal studies.

Search strategy Broad literature searches were performed, i.e. without being limited to predetermined health outcomes. This means that all health outcomes that have been studied were included in the searches. The following databases were searched up to 30 June 2004: MedLine, PsychInfo, Science Citation Index Expanded, Social Sciences Citation Index, Arts & Humanities Citation Index, ERIC, Social Services Abstracts and Sociological Abstracts. The literature searches were based on the search string (gaming OR computer game* OR video game* OR videogame* OR ((internet OR web OR on-line) AND (game*))). An asterisk means that all the possible endings of a word were included. The searches were conducted with the original search string and the addition (AND random*), (AND control*) and (AND cohort* OR longitudinal* OR prospective*)) respectivevly and, in MedLine with the addition (AND cohort studies [mesh]) where ‘cohort studies’ included all subordinated terms in the MESH tree (MedLine's hierarchy of key words). In MedLine, searches were also conducted with the original search string and ‘randomised controlled trial’ and ‘controlled clinical trial’ as limits. In PsychInfo the search for prospective cohort studies were supplemented with a search based on the original search string and longitudinal or prospective studies as limits. Supplementary searches for further studies were performed on the texts of the studies already identified.

Selection criteria The following four inclusion criteria were used: 1) the study was published in English in a scientific journal in which expert researchers had reviewed the work prior to publication (i.e. a peer-reviewed journal), 2) the study dealt with video or computer game playing as an exposure or evaluated an intervention aimed at reducing video or -6HEALTH EFFECTS OF VIDEO AND COMPUTER GAME PLAYING

computer game playing, 3) the study was designed so that the effect of video or computer game playing could be differentiated from the effects of other activities, and 4) the study was conducted as a randomised controlled trial, a controlled experiment or as a prospective longitudinal study. Two research fields were excluded because the findings could not be generalised to video and computer game playing in general. The first involved studies of video or computer game playing used for treatment, habilitation or rehabilitation (19 studies). The second field involved video or computer games used to supplement education in specific school subjects (8 studies).

Data collection and analysis In stage three, studies within the seven remaining fields were reviewed. Tables were created based on criteria from Källestål’s and Hedin’s handbook of systematic reviews in the field of public health (4). In the review of experiments, the following information was collected: type of study (if random distribution and if pre-measurement), drop-out rate and type of sample, the number of subjects, age, proportion females, the conditions (experimental and control groups, respectively), the titles of the video or computer games, playing time and playing environment, examined outcomes and follow-up time, and the findings. If researchers neglected to describe whether subjects were distributed randomly or not, it was assumed that they were not. The controlled studies are small and were conducted during a single day or over a period of a few weeks. Because of this, if drop-out rate were not discussed, it was assumed that there were no drop-outs. If the study presents differences between experimental and control groups with statistically significant effects on the 5-percent level, it is reported as an ‘effect’ in the tables. If the experiment included more than one control group, the group concerned is indicated in brackets. If the effect is only significant for one of the sexes this is reported as ‘only effect for...’. If effects are only attained when new variables are created afterwards, this is reported as ‘no effect’.


The type of psychological outcome studied in the experiments is often measured using instruments constructed by the research group in question. This means that instruments intended to measure the same thing may actually measure different underlying phenomena. The risk of this diminishes, the greater the number of studies examining the same outcome. In this report the general analysis and synthesis of experimental studies has therefore been limited to outcomes studied in at least three trials. In the review of prospective longitudinal studies, the following information was collected: number of participants and drop-out rate, distribution of drop-out, type of sample, age, proportion females, measurement of video or computer game playing, examined outcomes and the follow-up time, findings and control variables. One outcome is studied in two out of the four studies and is discussed under 'Findings'.


Results

A total of 30 studies were identified, 26 of which were experiments and 4 were prospective longitudinal studies. Six outcomes were studied in at least three experiments: spatial abilities, reaction time, aggressive play, aggressive thoughts/interpretations, aggressive feelings, and aggressive behaviours (excluding play). One outcome, overweight, was studied in two prospective longitudinal studies. The findings in the studies of these seven outcomes are summarised in Table 1. The full data is presented in the appended tables I-VII. The experimental studies that are not included in these tables are presented in the appended table VIII. The following sections presents the findings for the various outcomes more in detail.

Table 1. Effects of video or computer game playing on outcomes studied in at least three experiments or two prospective longitudinal studies. Number of studies where the predicted outcomes were observed/total number of studies, according to design RCT: pre and post measure ments

Controlled trials: pre and post measure ments

Better spatial abilities

4/4

1/1

I

Better reaction time

2/2

1/1

II

Predicted outcome

More aggressive play More aggressive feelings

0/1

More aggressive thoughts More aggressive behaviour

0/1

RCT: no pre measure ments

Controlled trials: no pre measurements

Prospective longitudinal studies

1/1

Appended table with studies

0/1

2/2

III

0/2

1/1

0/2

1/1

1/2

V

0/1

1/3

1/1

VI

IV

Increased incidence of overweight

0/2


VII

Spatial abilities and reaction time Positive effects of video and computer game playing on spatial abilities were seen in five out of five studies (see table 1 and the appended table I). Four of the studies were randomised controlled trials with pre-measurements. One of the studies was controlled with pre-measurements. The subjects in the experimental groups played video or computer games demanding spatial abilities for a total of one to five hours distributed over a period of some weeks. The control group either played video or computer games which did not demand spatial abilities or did not play any game at all. The study with the youngest participants included children with an average age of 5 while the study with the oldest participants included people with an average age of 22. All the studies reported positive effects on spatial abilities. The outcomes have been studied using standardised tests directly afterwards or one to three days after the intervention. In three of the studies the specific ability to mentally rotatate objects was examined using tasks similar to that in figure 2.

A

B

C

D

E

Figure 2. Sketched example of how mental rotation can be tested. The trial participants were asked to identify which of the figures B-E represented a rotated version of A (correct answers B and D).

Positive effects of playing computer games on reaction time were seen in three out of three studies (see table 1 and the appended table II). Two of the studies were randomised controlled trials with pre-measurements. One of the studies was a controlled experiment with pre-measurements. The experimental groups played computer games for a total of 14, 25 and 33 hours over a period of a few months and the outcome was examined directly after the intervention. In all the studies the participants were elderly. -10HEALTH EFFECTS OF VIDEO AND COMPUTER GAME PLAYING

Aggressive play The incidence of aggression in children’s play after video and computer game playing has been analysed in four studies (see table 1 and the appended table III). Three of the studies indicated increased aggression. No pre-measurements took place in these three studies but two of them were randomised. In these two studies, researchers studied the children’s choice of toys in a room where they had access to different toys. The children first played a computer game for 5-10 minutes and were then observed. In the first study the children, who were nine and ten years old, either played an aggressive computer game, a non-aggressive computer game, or a non-aggressive board game (5). The aggressive computer game led to girls playing more with a plastic warrior. In the second study, the children were five to seven years old (6). In this study the children who played the computer karate game ‘Karateka’ played more with a karate doll. The children who played the computer jungle game ‘Jungle Hunt’ in this study played more with lianas.

Aggressive feelings, thoughts and behaviours In addition to aggression in play, three other types of aggression outcome were studied: aggressive feelings, aggressive thoughts and aggressive behaviours. In the studies the experimental group generally played a violent computer game in a laboratory for 10-45 minutes after which the participants responded to questions on standardised questionnaires or were placed in a situation which allowed the researchers to study their behaviour towards another person. A recurrent situation involved the participants being asked to punish another person, for example by playing loud noises in the other person’s earphones. In these studies, predicted effects were only shown where there were no premeasurements available (see Table 1 and the appended tables IV-VI). The opposite effect was found in one study for aggressive thoughts: there was a reduction in the incidence of aggressive thoughts in the group that played the computer game, see Table V. -11HEALTH EFFECTS OF VIDEO AND COMPUTER GAME PLAYING

Overweight Two prospective longitudinal studies of effects on overweight were identified (see Table 1 and the appended table VII). In the first study, an increase in the incidence of overweight after one year was shown among girls who played computer games. This effect disappeared after two years. No effects were seen among boys after one or after two years. In the second study no effects were found.


Discussion

The review provides strong evidence that video and computer game playing has positive effects on spatial abilities and on reaction time. This assessment follows the practice for systematic literature reviews, where two studies fulfilling the quality criteria provide strong evidence for a claim (7). The effects on reaction time have only been studied with elderly people. Studies of spatial capacity have however included preschoolers and 8-11 year-olds as well as young adults. Spatial abilities are important for problem solving in general (8) and are especially important in certain technical and artistic contexts. Spatial ability is believed to be one of the most important parts of our intelligence and the most widespread intelligence tests measyre spatial ability alongside verbal and mathematical abilities (9). In recent decades average intelligence has increased. Some researchers associate this development with increased video and computer game playing among children (10). Effects on children's choices of aggressive toys have been shown in two studies which partly fulfil the quality criteria. According to systematic literature review practice, this provide limited evidence for a claim (7). As regards other types of aggression, none of the studies with pre-measurements indicate any effect. All in all, this implies limited evidence for video and computer game playing causing children to choose more aggressive toys - but no evidence for links between video and computer game playing and aggressive feelings, thoughts or behaviour, despite these outcomes being well studied. The fact that the choice of toys is influenced suggests that the content of the games does not go unnoticed by the children. Whether the choice of toys in the studies should be interpreted as a sign of aggression might, in the light of the other studies, warrant discussion. The two longitudinal studies presented concerning the effects of video and computer game playing on overweight provide no evidence for any such link, despite the fact that it is possible to show that TV-viewing does have such effects (11). One explanation might be that TV-viewing takes up considerably more time than video -13HEALTH EFFECTS OF VIDEO AND COMPUTER GAME PLAYING

and computer game playing. In one study, Swedish children played video and computer games for an average of 40 minutes per day while they spent around 2 hours and 40 minutes watching TV/videos (12).

Comparison with other reviews Subrahmanyam et al. have conducted a review of studies on different effects of both computer use and video and computer game playing. They too find that video and computer game playing has positive effects on spatial abilities. The evidence on aggresiveness is judged as “limited” (13). Five other reviews specifically analyse the effects on aggression (14-18). The conclusions in these five reviews are different. Three of them conclude that video and computer game playing leads to aggression (14-16). In these three reviews, the authors do not distinguish between studies with different designs or between different outcomes, but deal with all the material together. This means that lowquality studies influence the conclusions more than can be justified. In the remaining two reviews, the researchers distinguish between studies of high and low quality and deal with different outcomes separately. They then find evidence that play among young children is affected but no evidence for effects on other forms of aggressievness (17, 18). The link between overweight and video or computer game playing is analysed in a current review (19). The total effect there was not statistically significant which tallies with the conclusion in this review.


Authors

Anton Lager, Swedish National Institute of Public Health, performed the literature searches and has had the main responsibility for composing the report. Sven Bremberg, Swedish National Institute of Public Health, has been responsible for the study and took part in composing the report. Mia Danielson, Swedish National Institute of Public Health, and Ann-Margret Rydell, Department of Pschology, Uppsala University, have reviewed the text and provided valuable input. The report has been translated to English by Gary Watson.


References

1.

Nordström Å, ed. Upp till 18: fakta om barn och ungdom. Stockholm; Örebro:

Barnombudsmannen; Statistiska centralbyrån; 2001. [”Up to the Age of 18”, 2001 (avaliable in English from http://www.bo.se February 10, 2006)] 2.

Nordström Å, ed. Upp till 18: fakta om barn och ungdom. Stockholm; Örebro:

Barnombudsmannen; Statistiska centralbyrån; 2004. [”Up to the Age of 18”, 2004 (report in Swedish)] 3.

Rothman KJ, Greenland S. Modern epidemiology. 2 ed. Philadelphia: Lippincott-

Raven; 1998. 4.

Källestål C, Hedin A. Kunskapsbaserat folkhälsoarbete del 2. Stockholm: Statens

folkhälsoinstitut; 2004. [”Knowledge-based public health work Part 2” (avaliable in English from http://www.fhi.se February 10, 2006)] 5.

Cooper J, Mackie D. Video games and aggression in children. Journal of Applied

Social Psychology 1986;16(8):726-744. 6.

Schutte NS, Malouff JM, Post-Gorden JC, Rodasta AL. Effects of playing

videogames on children’s aggressive and other behaviors. Journal of Applied Social Psychology 1988; 1 8(5):454-460. 7.

Britton M. Evidenbaserad medicin. Så graderas en studies vetenskapliga

bevisvärde och slutsatsernas styrka. Läkartidningen 2000;97:4414-5. [”Evidencebased medicine. Grading the scientific values and strength of conclusions in clinical trials” (article in Swedish)] 8.

De Lisi R, McGillicuddy-De Lisi A. Sex differences in mathematical abilities and

achievement. In: McGillicuddy-De Lisi A, De Lisi R, eds. Biology, society, and behavior: the development of sex differences in cognition. Westport, Conn. ; London: Ablex Pub; 2001. 9.

Cianciolo AT, Sternberg RJ. Intelligence : a brief history. 1 ed. Oxford, UK ;

Malden, MA: Blackwell Pub.; 2004.


10. Greenfield PM. The cultural evolution of IQ. In: Neisser U, ed. The rising curve: long-term gains in IQ and related measures. Washington, DC: American Psychological Association; 1998. 11. Rydell A-M, Bremberg S. TV-konsumtion och barns hälsa och anpassning: en systematisk kunskapsöversikt. Stockholm: Statens folkhälsoinstitut; 2004. [“Television consumption and children’s health and adjustment” (avaliable in English from http://www.fhi.se February 10, 2006)] 12. Johnsson-Smaragdi U, d’Haenens L, Krotz F, Hasebrink U. Patterns of Old and New Media Use among Young People in Flanders, Germany and Sweden. European Journal of Communication 1998;13(4):479 - 501. 13. Subrahmanyam K, Greenfield P, Kraut R, Gross E. The impact of computer use on children’s and adolescents’ development. Journal of Applied Developmental Psychology 2001 ;22(1):7-30. 14. Anderson CA. An update on the effects of playing violent video games. J Adolesc 2004;27(1): 113-22. 15. Sherry JL. The effects of violent video games on aggression: A meta-analysis. Human Communication Research 2001 ;27(3):409-43 1. 16. Dill KE, Dill JC. Video game violence: A review of the empirical literature. Aggression & Violent Behavior 1 998;3(4):407-428. 17. Bensley L, Van Eenwyk J. Video games and real-life aggression: review of the literature. J Adolesc Health 2001 ;29(4):244-57. 18. Griffiths M. Violent video games and aggression: A review of the literature. Aggression & Violent Behavior 1 999;4(2):203 -212. 19. Marshall SJ, Biddle SJ, Gorely T, Cameron N, Murdey I. Relationships between media use, body fatness and physical activity in children and youth: a meta-analysis. Int J Obes Relat Metab Disord 2004;28(1 0): 123 8-46. 20. De Lisi R, Wolford JL. Improving children’s mental rotation accuracy with computer game playing. J Genet Psychol 2002;163(3):272-82. 21. Subrahmanyam K, Greenfield PM. Effect of video game practice on spatial skills in girls and boys. Journal of Applied Developmental Psychology 1994; 15(1): 13-32. -17HEALTH EFFECTS OF VIDEO AND COMPUTER GAME PLAYING

22. Perzov A, Kozminsky E. The Effect of Computer Games Practice on the Development of Visual Perception Skills in Kindergarten Children. Computers in the Schools 1989;6(3-4): 113-22. 23. Dorval M, Pepin M. Effect of playing a video game on a measure of spatial visualization. Perceptual & Motor Skills 1986;62(1):159-162. 24. De Lisi R, Cammarano DM. Computer experience and gender differences in under-graduate mental rotation performance. Computers in Human Behavior 1996;12(3): 351-361. 25. Goldstein JH, Cajko L, Oosterbroek M, Michielsen M, van Houten O, Salverda F. Video games and the elderly. Social Behavior & Personality 1997;25(4):345-352. 26. Dustman RE, Emmerson RY, Steinhaus LA, Shearer DE, Dustman TJ. The effects of videogame playing on neuropsychological performance of elderly individuals. J Gerontol 1992;47(3):P168-71. 27. Clark JE, Lanphear AK, Riddick CC. The effects of videogame playing on the response selection processing of elderly adults. J Gerontol 1 987;42(1):82-5. 28. Silvern SB, Williamson PA. The effects of video game play on young children’s aggression, fantasy, and prosocial behavior. Journal of Applied Developmental Psychology 1987;8(4):453-462. 29. Irwin AR, Gross AM. Cognitive tempo, violent video games, and aggressive behavior in young boys. Journal of Family Violence 1995; 10(3):337-350. 30. Calvert SL, Tan S-L. Impact of virtual reality on young adults’ physiological arousal and aggressive thoughts: Interaction versus observation. Journal of Applied Developmental Psychology 1994; 15(1): 125-139. 31. Anderson CA, Dill KE. Video games and aggressive thoughts, feelings, and behavior in the laboratory and in life. Journal of Personality & Social Psychology 2000;78(4): 772-790. 32. Scott D. The effect of video games on feelings of aggression. Journal of Psychology 1995; 129(2): 121-132.


33. Anderson CA, Ford CM. Affect of the game player: Short-term effects of highly and mildly aggressive video games. Personality & Social Psychology Bulletin 1986; 12(4): 390-402. 34. Graybill D, Kirsch JR, Esselman ED. Effects of playing violent versus nonviolent video games on the aggressive ideation of aggressive and nonaggressive children. Child Study Journal 1985; 15(3): 199-205. 35. Kirsh SJ. Seeing the world through Mortal Kombat-colored glasses: Violent video games and the development of a short-term hostile attribution bias. Childhood 1 998;5(2): 177-184. 36. Uhlmann E, Swanson J. Exposure to violent video games increases automatic aggressiveness. J Adolesc 2004;27(1):41 -52. 37. Graybill D, Strawniak M, Hunter T, O’Leary M. Effects of playing versus observing violent versus nonviolent video games on children’s aggression. Psychology – a Quarterly Journal of Human Behavior 1 987;24(3): 1-8. 38. Winkel M, Novak DM, Hopson H. Personality factors, subject gender, and the effects of aggressive video games on aggression in adolescents. Journal of Research in Personality 1987;21(2):21 1-223. 39. Bartholow BD, Anderson CA. Effects of violent video games on aggressive behavior: Potential sex differences. Journal of Experimental Social Psychology 2002;38(3): 283 -290. 40. Ballard ME, Lineberger R. Video game violence and confederate gender: Effects on reward and punishment given by college males. Sex Roles 1999;41(7-8):541-558. 41. Gordon-Larsen P, Adair LS, Popkin BM. Ethnic differences in physical activity and inactivity patterns and overweight status. Obes Res 2002; 10(3): 141-9. 42. O’Loughlin J, Gray-Donald K, Paradis G, Meshefedjian G. One- and two-year predictors of excess weight gain among elementary schoolchildren in multiethnic, low-income, inner-city neighborhoods. Am J Epidemiol 2000; 1 52(8):739-46. 43. Perez CE. Children who become active. Health Rep 2003; 14 Suppl: 17-28. 44. Robinson TN, Chen HL, Killen JD. Television and music video exposure and risk of adolescent alcohol use. Pediatrics 1998; 1 02(5):E54. -19HEALTH EFFECTS OF VIDEO AND COMPUTER GAME PLAYING

45. Deselms JL, Altman JD. Immediate and Prolonged Effects of Videogame Violence. Journal of Applied Social Psychology 2003;33(8): 1553-1563. 46. Chambers JH, Ascione FR. The effects of prosocial and aggressive videogames on children’s donating and helping. J Genet Psychol 1987; 148(4):499-505.


Study type, number of subjects (S) and drop-out rate RCT, pre- and postmeasurements 47 S, no drop-out

RCT, pre- and postmeasurements 61 S, 8% drop-out

RCT, pre- and postmeasurements, 68 S, no drop-out

RCT, pre- and postmeasurements, 70 S, no drop-out

Controlled experiment, pre- and post-measurements, 110 S, no drop-out

First author, year, reference and country De Lisi, 2002 (20), USA

Subrahmanyam, 1994, (21), USA

Perzov, 1989, (22), Israel USA

Dorval, 1986, (23), Canada

De Lisi, 1996, (24), USA

-21-

Two conditions, total playing time unclear (8 occasions, 5 “games” per time, 1-2 times a week for 4-6 weeks), laboratory Two conditions, total 60 min (2 x 30 min with a week inbetween), laboratory

Two conditions, total 135 min (3 x 45 min with 1 day to 1 week in-between, laboratory Four conditions, total 110 min (10 min/day for 11 days), at preschool

No. of conditions, playing time and environment Two conditions, total 330 min (11 times during one month), at school

1. Game requiring mental rotation: “Blockout” 2. Game not requiring mental rotation: “Solitaire

Mental rotation, 1-3 days after last game

1. Game requiring mental rotation: “Tetris” 2. Game not requiring mental rotation: “Carmen Sandiego” 1. Game requiring spatial abilities: “Marble Madness” 2. Game not requiring spatial abilities: “Conjecture” 1. Game requiring spatial ability: “Pac Man” 2. Game requiring spatial ability: Dodge ‘em 3. Game not requiring spatial ability: “Horse race”. 4. No game 1. Game requiring spatial abilities: “Zaxxon” 2. No game

Effect

Effect

Mental rotation, directly after

Effect (1 vs 3, 1 vs 4, 2 vs 3, & 2 vs 4) No effect

Effect

Effect

Findings

Mental rotation directly after

Spatial abilities directly after Planning ability directly after

Spatial abilities directly after

Examined outcome and follow-up period

The conditions and name of computer game

HEALTH EFFECTS OF VIDEO AND COMPUTER GAME PLAYING

Convenience sample from university college, 18-42 years, average age 21, 75% women

Convenience sample from university college, average age 22 years, 47% women

Convenience sample from four preschool classes, average age 5 years, % girls unclear

Convenience sample from a private school, 10.5-11.5 years, 54% girls

Type of sample, age and proportion of females All in grade 3 of a state school, 8-9 years, 49% girls

Table I. Experiments in which researchers have examined the effects of video and computer game playing on spatial abilities or the more specific spatial ability of mental rotation (bold type in table)

Appendix

Study type, number of subjects (S) and drop-out rate RCT, pre- and postmeasurements 22 S, no drop-out

RCT, pre- and postmeasurements 60 S, no drop-out

Controlled experiment, pre- and post-measurements, 14 S, no drop-out

First author, year, reference and country Goldstein, 1997, (25) Netherlands

Dustman, 1992, (26), USA

Clark, 1987, (27), USA

Reaction time, directly after

1. Two games: “Pac Man” and “Donkey Kong” 2. No game

Two conditions, total at least 14 hours (at least 2 h/week x 7 weeks) at a centre for older people

Convenience sample from a centre for older people, 57-83 years, 57% women


-22-

Reaction time, directly after Cognitive capacity, directly after Visual sensitivity, directly after Feelings, directly after

Effect

Reaction time, directly after Cognitive capacity, directly after Emotional well-being, directly after

Effect

No effect

No effect

Effect (1 vs 2 & 1 vs 3) No effect

Effect

No effect

Findings


1. Game S chose between 12 available games 2. Video film 3. Neither of these

The conditions and name of computer game 1. Game: “Super Tetris” 2. No game

Three conditions, total about 33 hours (3 h/week for about 11 weeks) at a laboratory

No. of conditions, playing time and environment Two conditions, total 25 hours (5 h/week for 5 weeks) in the home

Convenience sample of healthy older people in a town, 60-79 years, 62% women

Type of sample, age and proportion of females Convenience sample of healthy people in an apartment block for older people, 6990 years, 91% women

Table II. Experiments in which researchers have examined the effects of Video and computer game playing on reaction time (bold type in table)

Choice of aggressive toy, directly after Choice of “Active” toy Choice of “skill toy”

S divided into pairs where one played and the other observed: 1. Aggressive game: “Missile Command” 2. Non-aggressive game: “Pac Man” 3. Non-aggressive board game

1. Aggressive game: “Double Dragon” 2. Non-aggressive game: “Excitebike”. Ss took part in a competition afterwards designed to frustrate

Three conditions, 8 min + 2 min Introduction where necessary, in a lab

Two conditions, 20 min, in a lab

Convenience sample from schools, grades 4 & 5 (about 9-10 years) 48% girls

Convenience sample from two schools, 78 years, 0% girls

RCT, only postmeasurements, 84 S, no drop-out

Controlled experiment, only post-measurements, 60 S, 10 S dropped out beforehand

Cooper, 1986, (5), USA

Irwin, 1995, (29), USA


-23-

Choice of aggressive toy Choice of non-aggressive toy

1. Aggressive game “Karateka” 2. Non-violent game: “Jungle Hunt”

Two conditions, 5mins game & 5 observation, in preschool

Convenience sample from a preschool, 57 years, 52% girls

Physical and verbal aggression during play Choice of aggressive toy

Aggressive behaviour Reward behaviour

Choice of “silent toy”

Aggressive play Imagination Prosocial behaviour

1. Aggressive game: “Space Invaders”, S divided into pairs where one played and the other observed 2. Aggressive cartoon: “Road Runner”

RCT, only postmeasurements 31 S, no drop-out



Schutte, 1988, (6), USA

No. of conditions, playing time and environment Two conditions, 6 min, in a laboratory

Type of sample, age and proportion of women Convenience sample from a school, 4-6 years, 50% girls

Study type, number of subjects (S) and dropout rate Controlled experiment, pre- and postmeasurements, 28 S, no drop-out

First author, year, reference and country Silvern, 1987, (28), USA

table)

Effect on 4 of 6 submeasurements No effect

Only effect for girls (1 vs 2+3 together) No effect Effect for girls (1 and 2 together versus 3) and boys (1 vs 2 & 3 together) Only effect for girls (1 vs 2 and 1 vs 3) No effect No effect

Effect Effect

No effect No effect No effect

Findings

Table III. Experiments in which researchers have examined the effects of video and computer game playing on some aspect of aggression in play (bold type in the

Study type, number of subjects (S) and dropout rate RCT, pre- and postmeasurements, 36 S, no drop-out

Controlled experiment, pre- and postmeasurements 210 S, 5% drop-out

Controlled experiment, pre- and postmeasurements, 117 S, 3% drop-out

RCT, only postmeasurements, 60 S, No drop-out

First author, year, reference and country Calvert, 1994, (30), USA

Anderson, 2000, (31), USA

Scott, 1995, (32), Scotland


Three conditions, 20 min, in a lab

Convenience sample from university college, age unclear, unclear % women

1. Very aggressive game: “Zaxxon” 2. Aggressive game: “Centipide”. 3. No game

1. Very aggressive game: “Fatal Fury” 2. Aggressive game: “Overkill” 3. Non-aggressive computer game: “Tetrisc”

1. Aggressive game “Wolfenstein 3D” 2. Non-aggressive game: “Myst”

Aggressive feelings, directly after Nausea, directly after

1. Aggressive virtual reality game: “Dactyl Nightmare”, 2. Observation of S who played 3. No game but same movements”

Depressive feelings, directly after

Aggressive feelings, directly after Anxiety, directly after

Aggressive feelings, directly after the first 15 min Aggressive thoughts, directly after the second 15 min Aggressive behaviour directly after the last 15 min Aggressive feelings, directly after

No. of aggressive words directly afterwards




-24-

Three conditions, 10 min, in a lab

Two conditions, total 45 min (15 + 15 + 15 one week later) in a lab

Convenience sample from university college, age unclear, 50% women


No. of conditions, playing time and environment Three conditions, 4 min, on a funfair

Type of sample, age and proportion of women Convenience sample from private university college, average age 20.5 years, 50% women

Effect (1 & 2 together vs 3) Effect (1 vs 2 & 1 vs 3) No effect

No effect

No effect

No effect

No effect

Effect (1 vs 2&1 vs 3) Effect (1 vs 2 and 1 vs 3)

No effect

Findings

Table IV. Experiments in which researchers have examined the effects of Video and computer game playing on aggressive feelings (bold type in the table)

Controlled experiment, pre- and postmeasurements, 210 S, 5% drop-out

Controlled experiment, pre- and postmeasurements 116 S, no drop-out


Controlled experiment, only postmeasurements, 121 S, size of drop-out unclear Controlled experiment, only postmeasurements, 146 S, no drop-out

Andersson, 2000, (31) USA

Graybill, 1985, (34), USA

Kirsh, 1998, (35), USA

Uhlmann, 2004, (36), USA


Study type, number of subjects (S) and dropout rate

First author, year, reference and country

(bold type in the table)

No effect Aggressive behaviour, directly after Helpfulness, directly after Aggressive interpretations, direct after Ss were divided into pairs where one played and one observed 1. Two aggressive games from: “Berzerk”, “Gangster Alley” or “Boxing” 2. two non-aggressive games from “Fast Food”, “Basketball” or “Frogs and Flies”

-25-

Aggressive self-image, directly after

Two conditions, 14 min + 4 min introduction & exercises, in a lab


Effect on 3 of 6 submeasurement s Effect

Aggressive interpretations, directly after

1. Aggressive game: “Mortal Kombat II” 2. Non-aggressive game: “NBA JAM:TE” 1. Aggressive game: “Doom” 2. Non-aggressive game: Mahjongg”

Two conditions, 13 min +two min intro, in a lab

1. Aggressive game “Activision boxing” 2. Non-aggressive game: “Atari basketball”

No effect

Aggressive feelings directly after first 15 min Aggressive thoughts directly after second 15 min Aggressive behaviour, directly after the last 15 min Aggressive interpretation, directly after

1. Aggressive game: “Wolfenstein 3D” 2. Non -aggressive game: “Myst”

No effect No effect

Opposite effect on 1 of 6 submeasurement s

No effect

No effect

Findings



No. of conditions, playing time and environment Two conditions, total of 45 min (15 min+15 min + 15 min one week later) in a lab Two conditions, 8 min, in a lab


Convenience sample from school with university connection, grades 2, 4 and 6 (ca 7, 9 & 11 years), unclear % girls Convenience sample from a town of 150,000, 8-10 years, 44% girls Convenience sample of psychology students, 18 years “ or slightly older”, 55% women Convenience sample from a school, from grades 2 & 6 (ca 7-11 years) unclear % girls


Type of sample, age and proportion of women

Table V. Experiments in which researchers have examined the effects of Video and computer game playing on aggressive thoughts, interpretations or self-image



Table continues on next page

Convenience sample from a university, 18-23 years, 49% women


Bartholow, 2002, (39), USA

No effect

Aggressive behaviour, directly after

Aggressive behaviour, directly after Helpfulness, directly after Aggressive interpretations, directly after

1. Aggressive game: “Mortal Kombat” 2. Non-aggressive game: “PGA Tournament Golf”

Ss divided into pairs where one played and one observed 1. Two aggressive games from: “Berzerk”, “Gangster Alley” or “Boxing” 2. Two non-aggressive games from: “Fast Food”, “Basketball” or Frog and Flies”


Two conditions, 14 min + 4 min introduction and exercises, in a lab

-26-

Only effect on men

Aggressive feelings, directly after the first 15 min Aggressive thoughts, directly after the second 15 min Aggressive behaviour directly after the last 15 min

1. Aggressive game “Wolfenstein 3D” 2. Non-violent game: “Myst”

Two conditions, total of 45 min (15 + 15 + 15 min one week later) in a laboratory

No effect No effect

No effect

No effect

No effect

No effect No effect

Heart rate, directly after Aggressive behaviour, directly after

1. Very aggressive game 2. Aggressive game, 3. Nonaggressive game 4. No game

Findings



No. of conditions, playing time and environment Four conditions, playing time unclear in a laboratory


Convenience sample from a school, grades 2-6 (ca 7-11 years, unclear % girls

Convenience sample from a university college, age unclear, 50% women

Controlled experiment, re- and postmeasurements 210 S, 5% drop-out


Type of sample, age and proportion of women Convenience sample from a school, grade 8 (about 13 years), 50% girls

Study type, number of subjects (S) and dropout rate RCT, pre- and postmeasurements, 56 S, no drop-out

First author, year, reference and country Winkel, 1987, (38), USA

Table VI. Experiments in which researchers have examined the effects of Video and computer game playing on aggressive behaviour (bold type in the table)

Study type, number of subjects (S) and dropout rate RCT, only postmeasurements, 84 S, no drop-out

Controlled experiment, only post-measurements 119 S, no drop-out

First author, year, reference and country Cooper, 1986, (5), USA

Ballard, 1999, (40), USA

Table VI (cont).

-27-

Four conditions, playing time unclear, in a laboratory

No. of conditions, playing time and environment Three conditions, 8 min + 2 min introduction where necessary, in a laboratory

1. Very aggressive game: “Mortal Kombat II” 2. Aggressive game with blood: “Mortal Kombat” 3. Aggressive game without blood: “Mortal Kombat” 4. Non-aggressive game: “NBA jam”

Choice of aggressive toy, directly after Choice of “active” toy, directly after Choice of “skill toy”, directly after

Ss were divided into pairs when one played and one observed: 1. Aggressive game: “Missile Command” 2. Non-aggressive game: “Pac-Man” 3. Non-aggressive board game

Reward behaviour, directly after Aggressive behaviour, directly after

Choice of “silent” toy, directly after Aggressive behaviour, directly after Reward behaviour, directly after




Convenience sample from a university college, average age 21, 0% women

Type of sample, age and proportion of women Convenience sample from schools, grades 4 and 5 (ca 9-10 years), 48% girls

Effect (1 vs 4, 2 vs 4, & 3 vs 4) Effect (1 vs 4)

No effect

Effect for girls and boys separately (1 vs 2+3 together), not together Only effect for girls (1 vs 2, & 2 vs 3) No effect

Only effect for girls (1 vs 2+3 together) No effect

Findings

No of participants at T1 was 20,747. The analysis was based on the 14,438 who should have gone to high school a year later (T2). In addition to those who dropped out of high school, disabled persons, persons over 19 years old and native Americans were also excluded. No of participants at T1 was 4,016, one year later (T2) 2,318 and after a further year (T3) 633. There should have been 1,051 participants at T3

Gordon-Larsen, 2002, (41), USA

Table continues on next page

O´loughlin, 2000, (42), Canada

Number of participants and drop-out rate


studies (bold type in the table)

-28-

All in grades 4 and 5 at 16 schools in multiethnic low-income housing areas, 912 years, 51% girls at T2 and 50% girls at T3

Type of sample, age at T1 and % girls/women at T2 and T3 National representative sample, 11-19 years, 51 % girls

Computer gaming every day

Variable for TV or computer gaming Computer gaming ≥ 4h/week

Overweight: excess weight gain ((≥ 90th percentile in increase for that sex and age group, one (T2) and two years later (T3))

Examined outcome and follow-up period Overweight BMI ≥ 95th percentile, one year later


Drop-out participants were older, from larger households, more seldom from families of European background, and more seldom employed parents

Unclear how dropout was distributed

Drop-out distribution

Effect for girls at T2 but not for boys

No effect for entire population at T2.

No effect at T3.

No gender effects for whites, blacks or Hispanics (reduced risk for Asiatic boys, increased risk for Asiatic girls)

No effects for boys or girls in total.

Findings

Presented stratified for sex

Controlled for BMI at T1, “sociodemography”, physical activity, TV viewing, diet and school.

Presented stratified for sex and ethnicity

Controlled for age, total household income, parents’ level of education, domicile, smoking, civil status but not for BMI at T1

Control variables

Table VII. Prospective longitudinal studies on TV- and computer gaming as a risk factor for different health problems. Overweight has been examined in two

Number of participants and drop-out rate

There were 15,579 households (unclear no. of children). 16,903 children remained after drop-out. Children younger than 4 years were excluded. 14,226 were left. Of these, all data from both T2 and T3 was available for 8,387. 3,354 of these who were inactive at T1 and who either continued to be at both T2 and T3 or became active between T1 and T2 and continued to be at T3

Total population of 3,194 at T1. Special needs pupils and children who had failed in English were excluded and 2,777 should have participated. Of these, 2,609 took part. At T2 there was data for 1,533 participated


Perez, 2003, (43), Canada

Robinson, 1998, (44), USA

Table VII (cont)

Alcohol “debut” between T1 and T2 (18 months later). Persistent alcohol use, drank at T1, had increased lifetime consumption and drank ≥ one unit in the last month Computer gaming more than 7h/week

All in grade 9 at six state schools, average age of 14.6 years, 50% girls

-29-

Examined outcome and follow-up period Initiation of physically active lifestyle between T1 and T2 (two years later) and maintaining it until T3 (another two years later)

Variable for TV or computer gaming Computer gaming a few times a week or more

Type of sample, age at T1 and % girls/women at T2 and T3 National representative sample, 4-11 years, exact % of girls unclear


Drop-outs more often boys, older people, “Latino”, “AfricanAmerican” and others

Unclear how drop-out was distributed

Drop-out distribution

Controlled for alcohol debut at T1 (by stratification).

No effect

Control for age, sex, ethnicity and other media use

Controlled for physical activity at T1 by stratification. Control for BMI, sex, age, household income, health status, disability, asthma, self-confidence, participation in organised and unorganised sport, medical consultations, parents’ education, parents’ disability, smoking, proximity to green areas, housing area safety

No effect

No effect

Control variables

Findings

Study type, number of subjects (S) and dropout rate RCT, only postmeasurements, 92 S, 9% drop-out

RCT, only postmeasurements 59 S, 5% drop-out


First author, year, reference and country Deselms, 2003, (45), USA

Deselms, 2003, (45), USA

Chambers, 1987, (46), USA Ss in pairs: 1. Aggressive game against another S: “Boxing” 2. Aggressive game against computer: “Boxing” 3. Prosocial game with another S: “Smurfs” 4. Prosocial game alone: “Smurfs” 5. No computer game

Prosocial behaviour directly after Helpfulness directly after

Sensitivity for violence, directly after and 1 h after

Sensitivity for violence, directly after

1. Very aggressive game: “Mortal Kombat II” 2. Aggressive game: “Mortal Kombat” 3. Non-aggressive game: “NBA jam” 1. Very aggressive game “Mortal Kombat II” 2. Non-aggressive game: “NBA jam”




-30-

Five conditions, 10 min, at school

Two conditions, 30 min game + 10 min introduction, in a laboratory

Convenience sample of psychology students, average age 22, 47% women Convenience sample from state schools, 8-10 and 12-15 years, 50% girls

No. of conditions, playing time and environment Two conditions, 30 min + 10 min introduction, in a laboratory

Type of sample, age and proportion of women Convenience sample of psychology students, average age 23 years, 50%women

Table VIII. Experiments in which only odd outcomes were examined

Effect (1 vs 4, & 2 vs 4) No effect

Predicted effect for men, opposite effect for women

Only effect for men

Findings

Many children and young people play TV- or computer games on a regularly basis. To get a picture of the effects of playing those games, the Swedish National Institute of Public Health has performed a systematic review of available scientific studies on the issue. This systematic review shows that there is limited evidence for playing violent video and computer games causing children to choose aggressive toys. Available research does not provide any support for a link between video game playing and aggressive feelings, aggressive thoughts or aggressive behaviours – despite all these outcomes having been well studied. Moreover, the available longitudinal studies of video game playing and overweight do not support a link. At the same time, there is a strong support for video and computer game playing giving positive effects on cognitive abilities.


National Institute of Public Health Distribution SE-120 88 Stockholm

Fax +46 8 449 88 11 E-mail [email protected] Internet www.fhi.se

ISBN 978-91-7257-519-6

swedish national institute of public health

www.fhi.se