For centuries, corporal punishment was an acceptable and expected part of child rearing. In recent decades, however, corporal punishment has been branded outdated and needlessly violent. Nonphysical forms of discipline such as time-outs are recommended instead. A good deal of research supports the greater effectiveness of non-physical forms of discipline. However, the use of corporal discipline varies across cultural subgroups. Some research has shown that, within African-American communities, children raised with corporal discipline were less likely to display acting-out behavior, to get in trouble at school or with the police. It seems that corporal discipline can be effective when it is mild, predictable, performed for the purposes of discipline and not done out of anger. Corporal punishment becomes abusive when it is excessively harsh, causes ongoing pain or physical injury, is unpredictable or arbitrary, and is motivated by parental rage rather than the need to instill appropriate standards of behavior.