Holiday Internet Usage Time and the Risk of Internet Addiction Tendency among Working Adults in their 30s in Japan

Introduction: A positive association between Internet usage time and Internet addiction among adolescents and adults has been frequently reported; however, studies of working adults focusing on weekdays and holidays are limited. Therefore, this study aimed to elucidate the association between Internet usage time and psychometric tests among working adults in their 30s, focusing on weekdays and holidays. Methods: A total of 129 workers aged 30–39 years participated in this study. Participants completed a questionnaire and interview regarding psychometric tests, including Internet usage time, Internet addiction tendency, smartphone addiction tendency, depression tendency, and personality traits. A correlation analysis focusing on differences between weekdays and holidays was conducted. Results: The scores on Internet addiction scales are weakly positively correlated with holiday Internet usage time. The scores of smartphone addiction scales are also weakly positively correlated with the holiday Internet time. No correlation was found between weekdays Internet usage time and scores on Internet addiction scales. Conclusions: Internet usage time during holidays is associated with Internet addiction tendency among the working adult samples. Holiday Internet usage time could be a useful indicator of risk of Internet addiction. Our pilot findings provide clues to the mental health affected by the Internet, especially among adults.