Punishing children in a physical way does not improve their behaviour and instead increases behavioural difficulties, researchers suggest.
The findings suggest the link between physical punishment and increased behaviour problems is causal.
No study showed physical punishment reduced problem behaviour or promoted positive outcomes.
When looking at data over time, no improvements were found in children’s attention, cognitive abilities, relationships with others, reactivity to stress, prosocial behaviour or social competence among children who were physically punished.
The research, led by UCL and many international experts, focused on 69 studies worldwide which spanned 20 years.
The researchers followed children over time and analysed data on physical punishment and a range of different outcomes.
It suggests that across the world 63% of children between the ages of two and four, approximately 250 million children, are regularly subjected to physical punishment by their caregivers.
Researchers say so far 62 sovereign countries, including Scotland and Wales, have banned the practice and experts are calling for England, Northern Ireland and all countries to end the physical punishment of children in all settings including the home.
Scotland became the first part of the UK to ban smacking in November 2020 and Wales followed shortly after.
Lead author Dr Anja Heilmann, of the UCL Department of Epidemiology and Public Health, said: “Physical punishment is ineffective and harmful, and has no benefits for children and their families. This could not be clearer from the evidence we present.
“We see a definitive link between physical punishment and behavioural problems such as aggression and antisocial behaviour.
“Physical punishment consistently predicts increases in these types of behavioural difficulties.
“Even more worrying are findings that children who are the recipients of physical punishment are at increased risk of being subjected to more severe levels of violence.”
Senior author Elizabeth Gershoff, Amy Johnson McLaughlin Centennial Professor in Human Development and Family Sciences at the University of Texas at Austin, added: “Parents use physical punishment with their children because they think doing so will lead to better behaviour.
“But our research found clear and compelling evidence that physical punishment does not improve children’s behaviour and instead makes it worse.”
The study, published in The Lancet, found the detrimental outcomes associated with physical punishment occurred irrespective of the child’s sex, ethnicity, or the overall parenting styles of the caregivers.
Jillian van Turnhout, co-author of the paper and a former Senator in the Irish Parliament, added: “This review has documented compelling evidence that hitting children doesn’t work, and in many cases, it is harmful.
“A home should be a safe place for children, yet in many countries, the law can make it one of the most unsafe places for them.
“Countries need to do all they can to ensure that all children have equal protection from all forms of harm, including physical punishment.”