Author     Country Prevalence     Mean age     Age range       Gender preponderance Sample Year             Evaluation of IA
Johansson and Gotestam [13] Norway 2% 14.9 12-18 M > F 3237 2004 Young’s Diagnostic Questionnaire (telephone/mail)
Morahan-Martin and Schumache [20] USA 8.1% 20.72 Not addressed M > F 277 2000 Pathological Internet Use Scale
Anderson [29] USA 9.8% Not addressed Not addressed M > F 1078 2001 Internet use per day; assessment of academic, social or lifestyle problems
Yuen and Lavin [30] USA 15.2%* Not addressed 18+ Not addressed 283 2004 Questionnaire based on DSM-IV substance dependence
Leung [31] Hong Kong 37.9% 19.8 16-24 F > M 699 2004 Young’s Diagnostic Questionnaire (telephone)
Greenfield [32] USA/Canada 5.7% 33 8-85 M = F 17,251 1999 Virtual Addiction Survey (online)
Chou and Hsiao [33] Taiwan 5.9% 21.11 20-25 M > F 910 2000 Chinese Internet-Related Addictive Behavior
Inventory, version II / Young's Diagnostic Questionnaire
Kubey et al [34] USA 9.26% 20.25 18-45 M = F 576 2001 Self-reported Internet dependency and related psychological factors
Lin and Tsai [35] Taiwan 11.8% Not addressed Not addressed M > F 753 2002 Internet Addiction Scale for Taiwanese High Schoolers
Whang et al. [36] Korea 3.5% 26.74 20-50 M = F 13,588 2003 Modified Young’s Internet Addiction Scale (online)
Kaltiala-Heino et al.[37] Finland 1.4%-1.7% 15.6* 12-18 M > F 7229 2004 Questionnaire based on DSM-IV pathological gambling
Yoo et al.[38] Korea 0.9% 11.1 9-13 M > F 535 2004 Young’s Internet Addiction Test
Niemz et al. [39] UK 18% 21.5 Not addressed M > F 371 2005 Pathological Internet Use Scale (online)
Kim et al. [40] Korea 1.6% Not addressed 15-16 F = M 1573 2006 Young’s Internet Addiction Test
Aboujaoude et al.[41] USA 0.3%-0.7% 48.5 18+ Not addressed 2513 2006 Criteria based on DSM-IV disorders (telephone)
Pallanti et al. [42] Italy 5.4% 16.67 14-18 M = F 275 2006 Young’s Internet Addiction Test
Jang et al. [43] Korea 3.7%-5.1% 13.9 Not addressed M > F 851 2008 Young’s Internet Addiction Test
Ghassemzadeh et al.[44] Iran 3.8% Not addressed 14-16 Not addressed 977 2008 Young’s Internet Addiction Test
Lam, et al. [45] China 0.6%-10.2% Not addressed 13-18 M > F 1618 2009 Young’s Internet Addiction Test
Ghamari et al. [46] Iran 10.8 21.1* 19-23* M > F 426 2011 Young’s Internet Addiction Test
Durkee, et al. [47] Europe and Israel 4.4% 14.9 13-17 M > F 11,956 2012 Young’s Diagnostic Questionnaire
Poli and Agrimi [48] Italy 5.8% 16.4 14-21 M > F 2533 2012 Young’s Internet Addiction Test
Shek and Yu [49] China 26.7% 13.64 10-17 M = F 3580 2012 Young’s 10-Item Internet Addiction Test
*Calculated from data reported on the article
F: Female; M: Male
Table 1: Epidemiologic Data on the Prevalence of Internet Addiction.