Slapping a child has no benefits whatsoever, a leading consultant paediatrician has said.

According to Prof Alf Nicholson of Temple Street Children's University Hospital, parents should be advised that slapping "is not an effective strategy to alter a child's behaviour" and can have long-term damaging effects.

Corporal (physical) punishment has been banned in Ireland since 2015. Ireland is one of 52 countries worldwide to have introduced such a ban.

Prof Nicholson pointed out that since 2015, "compelling international evidence has since emerged to fully highlight the long-term effects of slapping children".

He said that recent evidence shows that slapping is clearly linked with a number of poor outcomes in adults including drug use, moderate to heavy alcohol consumption and suicide attempts.

Slapping is also linked with increased aggression and antisocial behaviour in childhood and adolescence.

"We have no figures as yet to say whether legislative change in Ireland has actually brought about a change in attitudes or behaviour in relation to slapping children, as legislation on its own is most unlikely to be effective. We do know from international evidence that, for both men and women, harsh physical punishment in childhood, including pushing, grabbing, shoving, slapping and hitting, is associated with antisocial behaviours in adulthood," Prof Nicholson explained.

He noted that recent evidence suggests that corporal punishment of toddlers is linked with subsequent aggressive behaviour, which can cause "a negative spiral that can lead to further slapping".

"The evidence is very strong indeed that slapping children is associated with adverse outcomes for the child. If the child is under 18 months, slapping can escalate to causing physical injury and repeated slapping has a wholly negative effect on the parent-child relationship.

"Slapping is associated with increased aggression in both pre-school and school-aged children, an increased risk of mental health disorders and cognition problems and more oppositional and defiant behaviour in the child," Prof Nicholson said.

However, he also acknowledged that slapping is not the only form of punishment that causes damaging effects.

Harsh verbal abuse before the age of 13 is linked with changes on MRI brain scans in adolescence, conduct problems and symptoms of depression.

When it comes to effective discipline, Prof Nicholson emphasised that parents should be advised that slapping should never be used.

"For many children, slapping merely increases aggression and anger instead of teaching responsibility and self-control. Parents are capable of seeing the value of ‘time outs' to positively modify behaviour in their children. Positive reinforcement should be the primary means of teaching acceptable behaviour," he insisted.

He said that positive reinforcement and limit setting are key and he called on parents to "always strive to redirect and set future expectations in the child".

"Parents should not use corporal punishment either in anger or frustration or as a punishment for poor behaviour, nor should they use verbal abuse or humiliation. Both have well recognised long-term deleterious effects on the child.

"Slapping is therefore not necessary, quite ineffective and has long-lasting effects. Having introduced legislation back in 2015, we need to continue to change attitudes and behaviours in parents and caregivers to ensure slapping is no longer considered acceptable in this country," he added.

Prof Nicholson made his comments in the July/August issue of the Irish Medical Journal.