Stepping up the game

Petry and colleagues 1 present an international consensus for assessing internet gaming disorder, an important and necessary effort in moving the field of internet gaming disorder further. First, this consensus on assessment may generate more consistency in future research on internet gaming disorder, a field which is characterized by inconsistency in the way internet gaming disorder is defined. This inconsistency can largely be explained by the lack of inclusion of gaming disorder as a psychiatric diagnosis, until now. With the inclusion of Internet gaming disorder as the sole non-substance addiction in the appendix of the DSM-5 2, the decision to come to an international consensus on how to assess internet gaming disorder is very timely. In this way, future studies can use the same assessments methods, which can inform and guide decision-making on whether inclusion of internet gambling disorder in coming revisions of the DSM-5 is warranted. The article presents a consensus on wording for the internet gambling disorder criteria. This is an important step as these questions can readily be used in a structured interview. A necessary next venue, which could be based on this consensus paper, is to develop a consensus on a questionnaire on internet gaming disorder. As presented in table 1 by Petry et al. 1, currently eight questionnaires have been used in published research. The suggested wording as presented in this table, e.g. for the third criterion, focuses on three potential ways in which tolerance for gaming is defined (1: feeling the need to play for increasing amounts of time, 2: play more exciting games; 3: using more powerful equipment). By dividing this question in three subsets of questions in a questionnaire, important information about the character of tolerance in internet gaming disorder could be gathered, which is relevant for further delineating this disorder. Importantly, the authors suggest to incorporate different wording for the internet gaming criteria for different age groups, as social and developmental aspects influence the manifestation of the dysfunction. The authors also suggest that by breaking down the all-inclusive items into discrete components, meeting of one of the components would make someone meet the criterion. This suggests that there is already consensus among the authors on how to define a potential internet gaming disorder questionnaire. Besides the suggested criteria for internet gaming disorder, another addition that could shed light on the clinical significance and impact of internet gaming disorder is the inclusion of the amount of time that is spent on internet gaming. This would parallel the measurement of quantity of use for substance use disorders. Although not a formal criterion for gambling disorder, the sole behavioral addiction currently incorporated in DSM-5, the definition of quantity of gambling is difficult: Quantity of gambling usually refers to a combination of the amount of money and/or the amount of time spent on gambling. For internet gaming disorder, the amount of time could be a clinical and objective indicator of how heavy the involvement in internet gaming is, and thus, what the clinical relevance is of someone who fulfils criteria for internet gaming disorder. An example of the clinical relevance of including such a quantitative measure is present in a study on the prevalence of pathological scratchcard gambling, which was performed as a prerequisite upon the introduction of this form of gambling in the Netherlands 3. From this study, it became apparent that pathological scratchcard gambling had little clinical relevance, as less than 20 Euros was spent per month among unique scratchcard gamblers. Treatment goals for substance use disorder often incorporate the quantity of use (e.g. the Alcohol Use Disorder Identification Test is recommended as a routine outcome measure for drinking-related outcomes [4; NICE guideline 115] and total alcohol consumption and heavy drinking days are some of the suggested primary outcome measures by the European Medicines Agency 5. A quantitative measure on internet gaming involvement could thus be an indicator of clinical relevance and a useful dimensional outcome measure for future intervention studies. In conclusion, the consensus article on assessing internet gaming disorder is an important step to move the research field of internet gaming disorder further. Further developments based on this paper, such as an internet gaming disorder questionnaire and implementation of a quantitative measure of gaming involvement could provide further venues. Thus, standardizing and improving assessment can have important consequences for research into the epidemiology, characterization, and clinical relevance of this disorder, which in turn could influence the future classification of internet gaming disorder. Anna E. Goudriaan is supported by an innovative research scheme grant (VIDI 016.136.354) from the Netherlands Organization for Health Research and Development, a government funding body. She has received funding from the Dutch Scientific Association and from ERAB (the European Foundation for Alcohol Research), which is an independent foundation that awards alcohol-related research after an independent scientific evaluation (peer reviewed), with guarantee of completely independent scientific expression (in accordance with the Dublin principles: http://www.api.or.at/sp/alcoholpolicy%20dokumente/dublinpriciples.pdf) 6. In the past she has received public funding from the binational program of the Dutch Scientific Organization—Division of Health Science and NIDA, from the Institute for Research on Pathological Gambling and Related Disorders (IRPG), an independent grantmaking organization affiliated with the Division on Addictions at the Cambridge Health Alliance, a teaching affiliate of Harvard Medical School and she has been paid for consultancy for TUV Austria.