Fewer kids are spanked today than in 1975, but nearly 80 percent of preschoolers are still spanked in the United States. And corporal punishment remains common around the world even though two dozen countries have banned it since 1979.

So say three separate, recently published studies of corporal punishment led by researchers at the University of North Carolina Injury Prevention Research Center.

Among the findings in the three studies:

• Rates of harsh physical discipline revealed by the surveys of families in the U.S., Egypt, India, Chile, the Philippines and Brazil were “dramatically higher” in all communities “than published rates of official physical abuse in any country.”
• Mothers with fewer years of education more commonly used physical punishment.
• 18 percent fewer children were slapped or spanked by caregivers in a survey of families in North and South Carolina compared to 1975. But nearly 80 percent of preschoolers were spanked and nearly half of children ages 8 and 9 were hit with an object such as a paddle or switch.

“The U.S., unlike most other high income countries, has had little change in the use of corporal punishment as commonplace," said Dr. Adam J. Zolotor, an assistant professor of family medicine in the UNC School of Medicine who conducted some of the research, in a news release. "Given the weight of evidence that spanking does more harm than good, it is important that parents understand the full range of options for helping to teach their children. A bit of good news is that the decline in the use of harsher forms of punishment is somewhat more impressive.”

The American Academy of Pediatrics is among the many groups that discourage spanking. The practice, experts say, can lose its impact after a while; lead to physical struggles; and increase aggression and anger instead of teaching responsibility.

"It is true that many adults who were spanked as children may be well-adjusted and caring people today," the academy says on its website HealthyChildren.org. "However, research has shown that, when compared with children who are not spanked, children who are spanked are more likely to become adults who are depressed, use alcohol, have more anger, hit their own children, hit their spouses, and engage in crime and violence."

The academy also offers some suggestions for discipline including time-outs, consequences and other tips to make discipline more effective.

But there are obviously many people (the majority of parents evidently) who believe spanking is a necessary form of discipline. The conservative Family Research Council says it can fall well within the boundaries of "loving discipline."

Click here to read more about the UNC studies and other findings, including a review of laws and attitudes on corporal punishment around the world.

So have you spanked your kids? Has it worked for you? Or does it cause more problems later on?

Copyright 2010 by Capitol Broadcasting Company. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.