You have seen a toddler in clinic, and as a “by the way” on leaving, the mother tells you that the child has a very red bottom and cries on defaecation although she is not constipated. On examination you see the classic signs of perianal dermatitis. You prescribe penicillin, and subsequent culture confirms streptococcal A infection. After clinic the staff grade doctor, who works with you and has expertise in child protection informs you that you should be considering sexual abuse as an issue. You decide to find out if there is an association between perianal dermatitis and child sexual abuse.