  The proliferation of harmful content on online social media platforms has
necessitated empirical understandings of experiences of harm online and the
development of practices for harm mitigation. Both understandings of harm and
approaches to mitigating that harm, often through content moderation, have
implicitly embedded frameworks of prioritization - what forms of harm should be
researched, how policy on harmful content should be implemented, and how
harmful content should be moderated. To aid efforts of better understanding the
variety of online harms, how they relate to one another, and how to prioritize
harms relevant to research, policy, and practice, we present a theoretical
framework of severity for harmful online content. By employing a grounded
theory approach, we developed a framework of severity based on interviews and
card-sorting activities conducted with 52 participants over the course of ten
months. Through our analysis, we identified four Types of Harm (physical,
emotional, relational, and financial) and eight Dimensions along which the
severity of harm can be understood (perspectives, intent, agency, experience,
scale, urgency, vulnerability, sphere). We describe how our framework can be
applied to both research and policy settings towards deeper understandings of
specific forms of harm (e.g., harassment) and prioritization frameworks when
implementing policies encompassing many forms of harm.
