Beyond Platforms: Assessing the Value of a Cross-Platform Perspective on SNS and Mental Health

Research on social networking sites (SNS) and mental health has produced highly heterogeneous findings, often attributed to differences between platforms such as Facebook, Instagram, and TikTok. In response, cross-platform comparisons are increasingly proposed as a promising analytical direction, yet their actual conceptual and explanatory value remains unclear. Rather than aiming to identify platform-specific effects, this Short Report critically examines whether a cross-platform perspective meaningfully advances our understanding of SNS-mental health associations. To this end, we conduct a brief scoping review of quantitative studies that explicitly compare multiple SNS platforms within the same design (N = 14). The review reveals substantial methodological and conceptual inconsistencies across studies, suggesting that platform-level comparisons alone rarely clarify observed heterogeneity. We argue that future research would benefit from moving beyond platform labels toward a feature- and affordance-based cross-platform approach that is more closely aligned with psychological theory.