groups, and across time. The terms abuse and maltreatment are often used interchangeably in the literature. Child maltreatment can also be an umbrella term covering all forms of child abuse and child neglect. Defining child maltreatment depends on prevailing cultural values as they relate to children, child development, and parenting. Definitions of child maltreatment can vary across the sectors of society which deal with the issue, such as child protection agencies, legal and medical communities, public health officials, researchers, practitioners, and child advocates. Since members of these various fields tend to use their own definitions, communication across disciplines can be limited, hampering efforts to identify, assess, track, treat, and prevent child maltreatment. In general, abuse refers to (usually deliberate) acts of commission while neglect refers to acts of omission. Child maltreatment includes both acts of commission and acts of omission on the part of parents or caregivers that cause actual or threatened harm to a child. Some health professionals and authors consider neglect as part of the definition of abuse, while others do not; this is because the harm may have been unintentional, or because the caregivers did not understand the severity of the problem, which may have been the result of cultural beliefs about how to raise a child. Delayed effects of child abuse and neglect, especially emotional neglect, and the diversity of acts that qualify as child abuse, are also factors. The World Health Organization (WHO) defines child abuse and child maltreatment as "all forms of physical and/or emotional ill-treatment, sexual abuse, neglect or negligent treatment or commercial or other exploitation, resulting in actual or potential harm to the child's health, survival, development or dignity in the context of a relationship of responsibility, trust or power." The WHO also says, "Violence against children includes all forms of violence against people under 18 years old, whether perpetrated by parents or other caregivers, peers, romantic partners, or strangers." In the United States, the Centers for Disease Control and Prevention (CDC) uses the term child maltreatment to refer to both acts of commission (abuse), which include "words or overt actions that cause harm, potential harm, or threat of harm to a child", and acts of omission (neglect), meaning "the failure to provide for a child's basic physical, emotional, or educational needs or to protect a child from harm or potential harm". The United States federal Child Abuse Prevention and Treatment Act