Revisiting the Knowledge Gap Hypothesis: A Meta-Analysis of Thirty-Five Years of Research

This knowledge gap meta-analysis examines (a) average effect size of the gap, (b) impact of media publicity, and (c) moderators of the gap. Positive correlation between education and level of knowledge ( r = .28) was found, with no differences in the size of the gap (a) over time and (b) between issues of higher and lower publicity. However, gap magnitude was moderated by topic, setting, knowledge measure, and study design, but not by publication status, country, and sampling method. Relatively smaller gaps were found for (a) health-science topics compared to social-political topics and (b) local/personal issues compared to international issues.