The exclusion criteria are the requirements used for exclusion of participants from this study. The participants were excluded in this experiment when they:
- • Failed to meet the criteria of written consent
- • Failed to meet the criteria mentioned in the inclusion list
Sample Size Computation
The sample size of computation for this study was not predefined because this was a pilot study. Further research on this topic may be needed to properly compute the sample size using the mean differences among the three groups of this study, which were reported in the final year project (FYP) report available at UTP Institutional Repository (http://eprints. utp.edu.my/).
Experimental Video Game Contents
There are many types of content in video games that may have adverse psychological effects, namely, violence, sexual themes, substances, and profanity. In this project, violent content was selected by using the game Killzone 3. Violence is defined as “acts in which the aggressor causes or attempts to cause physical injury or death to another character.”2 Each violent scene was counted once with the following circumstances:
- • continuous attack with violent acts
- • when a character hit the opponent multiple times in an attack with violent magic or spinning attack, etc.
- • condition of many characters such as group battle
The level of violence in video games is measured by the amount of blood existing in the game. In video games, the blood that reflects the violence is defined as “a red fluid originating from an injured human or any color fluid originating from an injured creature.” The level of blood is coded as “animated blood,” realistic blood,” or “blood and gore.”21
In this project, a violent video game was used. However, there are video games that have contents such as sexual themes, substances, and profanity. In games with sexual themes, the sexuality traits include the size and shape of the body character, the attire, and the parts of exposure. Drugs, alcohol, tobacco, and gambling comprise the addictive substances and behavior category. Lastly, one of the video contents is the practice of profanity in song lyrics, either spoken or written. It is considered that profanity is the “use of abusive and vulgar language and obscene gestures.” 21