Freud and others have assumed that a preference for BDSM is a consequence of childhood abuse. Research indicates that there is no evidence for this claim. Some reports suggest that people abused as children may have more BDSM injuries and have difficulty with safe words being recognized as meaning stop the previously consensual behavior, thus, it is possible that people choosing BDSM as part of their lifestyle, who also were previously abused, may have had more police or hospital reports of injuries. There is also a link between transgender individuals who have been abused and violence occurring in BDSM activities.