The most recent update to the American Psychiatric Association’s (APA) Diagnostic and Statistical Manual of Mental Disorders (DSM-5) included Internet Gaming Disorder as a new potential psychiatric condition that merited further scientific study. The present research was conducted in response to the APA Substance-Related Disorders Working Group’s research call to estimate the extent to which mischievous responding—a known problematic pattern of participant self-report responding in questionnaires—is relevant to Internet Gaming Disorder research. In line with a registered sampling and analysis plan, findings from two studies (ntot= 11,908) provide clear evidence that mischievous responding is positively associated with the number of Internet Gaming Disorder indicators participants report. Results are discussed in the context of ongoing problem gaming research and the discussion provides recommendations for improving the quality of scientific practice in this area.