[Smartphone addiction: French validation of the Internet Addiction Test-Smartphone version (IAT-smartphone) and...

Since their first appearance in 1992 smartphones have improved constantly, and their use, combined with the rapid spread of the Internet, has increased dramatically. The recent emergence of this technology raises new issues, at both individual and societal levels. Several studies have investigated the physical and psychological harm that may be caused by smartphones. The issue of excessive smartphone use as an addictive disorder is frequently raised and debated, although it is not acknowledged in international classifications. In France, there is no validated assessment tool for smartphone addiction. Therefore, the aims of this research were: to validate a French translation of the Internet Addiction Test-smartphone version (IAT-smartphone); to study the links between smartphone addiction, Internet addiction, depression, anxiety and impulsivity.

Two hundred and sixteen participants from the general population were included in the study (January to February 2016), which was available online using Sphinx software. We assessed smartphone addiction (French version of the Internet Addiction Scale - smartphone version, IAT-smartphone), specificity of smartphone use (time spent, types of activity), Internet addiction (Internet Addiction Test, IAT), impulsivity (UPPS Impulsiveness Behavior Scale), and anxiety and depression (Hospital Anxiety and Depression scale, HAD). We tested the construct validity of the IAT-smartphone (exploratory factor analysis, internal consistency, non-parametric correlation tests for convergent validity). We also carried out multiple linear regressions to determine the factors associated with IAT-smartphone.

Mean age was 32.4±12.2 years; 75.5% of the participants were women. The IAT-smartphone had a one-factor structure (explaining 42 % of the variance), excellent internal consistency (α=0.93) and satisfactory convergent validity. Smartphone addiction was associated with Internet addiction (ρ=0.85), depression (ρ=0.31), anxiety (ρ=0.14), and some impulsivity subscales, including "negative urgency" (ρ=0.20; P<0.01), "positive urgency" (ρ=0.20; P<0.01), and "lack of perseverance" (ρ=0.16; P<0.05). Age was negatively associated with the IAT-S total score (ρ=-0.25; P<0.001), and there was a non-significant difference between the IAT-S total scores of men and women (29.3±10.2 vs. 32.7±12.4; P=0.06). Multiple linear regression showed that age, anxiety, depression, average time spent on the smartphone, impulsivity and Internet addiction explained 71.4 % of the variance of IAT-smartphone scores. However, this score dropped to 13.2 % when Internet addiction was removed from the model. This variable alone explained 70.8 % of the IAT-smartphone scores.

The French version of the IAT-smartphone is a reliable and valid questionnaire to assess smartphone addiction. This addiction appears to be strongly linked to anxiety, depression and impulsivity. The strong association between smartphone addiction and Internet addiction suggests that smartphone addiction is one of the many forms of Internet addiction. In fact, smartphones may not be the object of the addiction but rather a medium facilitating Internet access as it makes it possible to connect anywhere anytime. This raises the issue of the potential role of smartphones in speeding up and facilitating the development of Internet addiction.