Generative AI Makes Creative Output More Homogeneous

Does using generative AI make creative outputs more homogeneous? As creative practice increasingly involves using generative AI, concerns have emerged that creative outputs may become more homogeneous across users, even when individual creativity improves. We address this concern through a systematic review and meta-analysis of empirical studies on homogenization in human–AI co-creation (19 studies, 61 effect sizes). Results reveal a small but statistically significant homogenization effect associated with AI use ($d = .334$). The effect is robust across sensitivity analyses and not explained by publication bias. Rather than indicating a loss of creativity, the findings point to a reorganization of creative diversity in human–AI co-creation: subtle in isolated instances, but consequential through widespread engagement with similar AI systems.