However, the study also has some limitations.
First, the study uses self-report data, which is known to
carry the risk of bias [53]; this should be taken into
account when comparing estimates with external
outcome variables, such as the number of people reporting
for clinical treatment with game addiction as the
main complaint. Secondly, the ‘hours per week’ variable
was the result of a multiplication and might be affected
by ceiling effects; as such, it should be viewed as an estimate
and not as an absolute value.