Take-down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. Heritability and polygenic predictionIn the EUR sample, the SNP-based heritability (h 2 SNP ) (that is, the proportion of variance in liability attributable to all measured SNPs)

The internet today has become an integral part of daily life that facilitates communication, education, and entertainment. The behavioral pattern of excessive internet usage has similarities to substance addiction, such as tolerance, withdrawal, repeated failure to reduce or quit, and impairment in daily life. Yet, there is no consistent physiological change that accompanies excessive use of the internet, as there is in excessive substance use. Neurological and neuroimaging studies of excessive internet users show biological changes in the prefrontal cortex that are similar to those found in other addictive syndromes. Brain structure changes also occur in the temporal cortex and ventral striatum, compromising executive function in planning and reasoning and increasing impulsive risk, resulting in loss of control over internet use. Of all the potential online applications known to cause addiction, only internet gaming disorder has been selected in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) as a condition for further study.

Background Internet addiction is a serious problem that can negatively impact both the physical and mental health of individuals. The Internet Addiction Test (IAT) is the most common used instrument to screen internet addiction worldwide. This study sought to investigate the psychometric properties of an Indonesian version of the IAT. Methods The IAT questionnaire was made the focus of forward translation, expert panel discussions, back translation, an item analysis (30 subjects), a pilot study (385 subjects), and field testing (643 subjects). Factor structure was analysed by exploratory (EFA) and confirmatory factor (CFA) analyses, whereas reliability was measured with Cronbach’s alpha coefficient. Results Factor analysis revealed that the Indonesian version of IAT, consisted of 3 domains, and had good validity (χ2 p < 0.001; RMSEA = 0.076; CFI = 0.95; SRMR = 0.057, and AIC = 784.63). The Cronbach’s alpha score is 0.855. A significant association was also observed between the level of internet addiction with gender (p = 0.027) and the duration of internet use per day (p = 0.001). Conclusion The Indonesian version of IAT provides good validity and reliability in a three-dimensional model. Therefore, it can be utilised as a tool for screening internet addiction in the Indonesian population.