Chris Ferguson, PhD
The early Fall saw the release of two meta-analyses, one mine (Ferguson, 2015a), published in Perspectives on Psychological Science; the other was the final report by the controversial APA task force on video games (APA, 2015). True to form for the video game debates to date, the two metas reached differing conclusions, except for violent crime which both agreed could not be linked to violent video games.
With the “Angry Birds” meta, I examined the effects of video games, including violent ones on child and youth samples specifically (excluding college student samples). Outcomes examined included aggressive behavior, prosocial behavior, depression, ADHD, and academic performance. Results indicated that, with other factors controlled, video games including those with violent content appear to have minimal impact on children and adolescents on the examined outcomes. Further, publication bias, particularly for aggression studies, and citation bias, the tendency to only cite studies supporting personal beliefs, continue to be major problems for this field. This phenomenon can indicate researcher expectancy effects that could influence study results particularly when many outcome measures are unstandardized (Elson et al., 2014). Indeed, scholars who were prone to citation bias tended to produce higher effect sizes than those who produced more balanced literature reviews. Given that citation bias is widely recognized as a questionable and potentially unethical researcher practice (Babor & McGovern, 2008), our field needs to do more to push for honest and clear literature reviews. This is not to say authors should not be free to argue for their theoretical positions one way or another, only that to make such arguments without acknowledging even the existence of non-supportive data should be considered unscientific.
Perspectives on Psychological Science included comments from other scholars ranging from the supportive (Markey, 2015) to the self-described “angry” (Rothstein & Bushman, 2015), as well as my replies to the same (Ferguson, 2015b). An interesting methodological issue to emerge from this exchange is the evident weakness of many meta-analyses that rely on bivariate correlations for effect sizes. It is well understood that bivariate correlations tend to be spuriously high, yet many meta-analyses continue to rely on them. This risks considerable misinformation when these meta-analyses are communicated to the scientific community or general public. Some scholars have argued for years that meta-analyses of correlational studies should consider standardized regression coefficients or partial correlations rather than bivariate correlations (Savage & Yancey, 2008). In my reply (Ferguson, 2015b) I conducted some further analyses that indicated that bivariate correlations are often poorly suited for meta-analyses, whereas partial correlations and standardized regression weights often work better. Of course each meta-analysis must consider this on a case-by-case basis, but in the future more effective meta-analyses should also consider using better-controlled effect sizes when examining hypotheses.
The APA’s (2015) own task force meta-analysis was released to great controversy. In 2013, 238 scholars (including many Division 46 members) wrote to the APA, raising concerns about this task force and asking the APA to retire all policy statements on video games. Unfortunately, the task force made no effort to engage this large group of scholars. Concerns persisted that the task force members had too many conflicts of interest and that many of them had taken public anti-game positions in the past (see Wofford, 2015 for some excellent coverage). Further, the APA task force included only 18 studies in their meta-analysis (including college student samples, as opposed to 101 studies of children and adolescents only in the Angry Birds meta). The task force also appeared to have engaged in a voting procedure (pages 8-9) which excluded a large number of null studies for unclear reasons. A Council member present for the vote to “accept” the task force report has since written that the vote came after the exhaustive sessions on the Hoffman report following which Council members were very tired, with no discussion. From that description it isn’t clear how many Council members had read the task force report (Krause, 2015).
One thing positive about the APA task force report is that this is probably the first report by a professional advocacy organization to acknowledge that video game violence can’t be linked to violent crime. But the non-transparent and unresponsive task force, the apparent biases in its development and the resultant low-quality meta-analysis arguably foster, rather than ease criticisms that APA has reflexively engaged in anti-media bias and rhetoric, while “stacking the deck” for policy positions it may view as favorable for itself. Either way, the video game debate rages on, meta-analyses be damned!
Babor, T. F., & McGovern, T. (2008). Dante’s inferno: Seven deadly sins in scientific publishing and how to avoid them. In T. F. Babor, K. Stenius, S. Savva, & J. O’Reilly (Eds.) Publishing addiction science: a guide for the perplexed (2nd edition), pp. 153-171. Essex, UK: Multi-Science Publishing Company, Ltd.
Elson, M., Mohseni, M., Breuer, J., Scharkow, M., & Quandt, T. (2014). Press CRTT to measure aggressive behavior: The unstandardized use of the competitive reaction time task in aggression research. Psychological Assessment, doi:10.1037/a0035569
Ferguson, C. J. (2015a). Do angry birds make for angry children? A meta-analysis of video game influences on children’s and adolescents’ aggression, mental health, prosocial behavior and academic performance. Perspectives on Psychological Science, 10, 646-666. doi: 10.1177/1745691615592234
Ferguson, C. J. (2015b). Pay no attention to that data behind the curtain: On angry birds, happy children, scholarly squabbles, publication bias and why betas rule metas. Perspectives on Psychological Science, 10, 683-691. DOI: 10.1177/1745691615593353
Krause, M. (2015). Inversion: Reporting on the 2015 APA Council of Representatives meeting. BNCP, 33(3), 14-15.
Markey, P. (2015). Finding the middle ground in violent video game research: Lessons from Ferguson. Perspectives on Psychological Science, 10, 667-670. doi: 10.1177/1745691615592236
Rothstein, H., & Bushman, B. (2015). Methodological and reporting errors in meta-analytic reviews make other meta-analysts angry: A commentary on Ferguson (2014). Perspectives on Psychological Science, 10, 677-679. doi: 10.1177/1745691615592235
Savage, J., & Yancey, C. (2008). The effects of media violence exposure on criminal aggression: A meta-analysis. Criminal Justice and Behavior, 35, 1123-1136. doi: 10.1177/0093854808316487