Table 1.

Recent studies examining the relationship between internet usage and primary headache disorders.

Study	Type of study	Number and type of participants	Test used to measure Internet PIU	Proportion of PIU	Association between PIU and headaches
Cerutti et al. (37)	Cross-sectional population-based	841 adolescents	Young’s Internet Addiction Test (IAT)	Mobile only abusers: 26.0%; Internet only abusers: 14.9%; Abusers of both media: 19.5%	No significant relationship between headaches and the internet/mobile phone addiction.
Tepecik et al. (38)	Cross-sectional	200 children	Internet Addiction Scale (IAS)	3%	No relationship between IA and headache.
Corrêa et al. (39)	Cross-sectional	420 university students	Brazilian version of Internet Addiction Test (IAT)	20%	Signifcant relationship between IA and headache severity.
Demirer et al. (40)	Cross-sectional	647 university students	Turkish version of Young’s 20-item Internet Addiction Test (IAT)	5.6%	Moderately strong relationship between headache severity and the YIAT score.
Średniawa et al. (41)	Cross-sectional	200 high school graduates	Young’s Internet Addiction Test (IAT)	7%	Significant relationships between the level of Internet addiction and headache.