Under Ohio workers’ compensation law, for a claim to be allowed, a physical injury or disease, whether caused by external accidental means or accidental in character, must be sustained in the course of and arising out of employment. Therefore, if no physical injury or disease exists, then no workers’ compensation claim exists. Additionally, Ohio law specifies what may not be an injury, including self-inflicted injuries, injuries sustained due to horseplay, mental health conditions without a pre-existing physical injury or disease, natural deterioration or pre-existing conditions. However, before making any determination, a BWC claims service specialist (CSS) researches all claims to assure that legal requirements have been met. In particular, the CSS determines if there is a causal relationship between the injury or disease and the injured worker’s employment. Establishing causality relies on statements from the injured worker, employer and any witnesses, and, especially, all medical evidence (i.e., progress notes, diagnostic reports, etc.) submitted by any treating providers.