Some people have serious problems controlling
their Internet and video game use. The DSM-5 now
includes a proposal for ‘Internet Gaming Disorder’
(IGD) as a condition in need of further study. Various
studies aim to validate the proposed diagnostic
criteria for IGD and multiple new scales have been
introduced that cover the suggested criteria. Using a
structured approach, we demonstrate that IGD
might be better interpreted as a formative construct,
as opposed to the current practice of conceptualizing
it as a reflective construct. Incorrectly approaching a
formative construct as a reflective one causes serious
problems in scale development, including:
(i) incorrect reliance on item-to-total scale correlation
to exclude items and incorrectly relying on indices
of inter-item reliability that do not fit the
measurement model (e.g., Cronbach’s α);
(ii) incorrect interpretation of composite or mean
scores that assume all items are equal in contributing
value to a sum score; and (iii) biased estimation
of model parameters in statistical models. We show
that these issues are impacting current validation
efforts through two recent examples. A reinterpretation
of IGD as a formative construct has broad consequences
for current validation efforts and provides
opportunities to reanalyze existing data. We discuss
three broad implications for current research:
(i) composite latent constructs should be defined
and used in models; (ii) item exclusion and selection
should not rely on item-to-total scale correlations;
and (iii) existing definitions of IGD should be
enriched further.