WASHINGTON, April 26 (UPI) -- Although it remains a common method of discipline, a review of 50 years of research shows spanking has overall detrimental effects on children later in life.
Researchers at the University of Texas at Austin and and the University of Michigan reviewed the literature and found the more children were spanked, the more likely they were to not listen to their parents, to act in anti-social ways, to be aggressive and have other mental health problems.
As many as 80 percent of parents around the world discipline their children with spanking, defined as an open-handed hit on the behind or extremities.
Unlike some previous studies, researchers at the two universities focused on spanking and did not consider instances of other forms of physical discipline, regardless of whether they are considered abusive or not. This, they say, gives a better picture of the widely accepted disciplinary act, without needing to consider the effects of abuse.
"We as a society think of spanking and physical abuse as distinct behaviors," Dr. Elizabeth Gershoff, an associate professor of human development and family sciences at the University of Texas at Austin, said in a press release. "Yet our research shows that spanking is linked with the same negative child outcomes as abuse, just to a slightly lesser degree."
For the study, published in the Journal of Family Psychology, the researchers reviewed 111 studies that included 160,927 children who were measured on 17 effects of spanking.
Spanking was strongly associated with 13 of 17 outcomes, with children strongly tending toward detrimental outcomes. In addition, spanking was not associated with either immediate or long-term compliance -- which is the entire purpose of spanking.
In addition to being more likely to exhibit anti-social behavior and have other mental health issues, parents who were spanked as children are more likely to endorse and use spanking as a disciplinary measure.
The reinforcement of passing the method from generation to generation is not based on efficacy, however, and is instead based on automatic practice, despite research over the last half century showing that spanking is a less than ideal disciplinary decision.
"The upshot of the study is that spanking increases the likelihood of a wide variety of undesired outcomes for children," said Dr. Andrew Grogan-Kaylor, an associate professor in the school of social work at the University of Michigan. "Spanking thus does the opposite of what parents usually want it to do."