Damian Sendler: A growing number of people believe that physical punishment is harmful to children. The findings of 69 prospective longitudinal studies are summarized in this narrative review to help practitioners and policymakers understand the long-term effects of physical punishment. Seven major themes emerged from our investigation. To begin, research shows that children who are subjected to physical punishment develop more behavioral issues over time. Second, long-term effects of physical punishment are not positive. As a final point, physical punishment raises the likelihood of child welfare involvement. When children engage in deviant behavior, they are only likely to be punished by their parents in the form of physical discipline. In quasi-experimental studies, physical punishment predicts worsening behavior over time. As a final point, the link between physical punishment and negative outcomes for children is strong regardless of the characteristics of both the child and the parent. It appears that a dose–response relationship exists. These findings show that physical punishment is harmful to children and that policy changes are needed.
Damian Jacob Sendler: UNICEF-Lancet Commission1 on children has highlighted social, economic, commercial and environmental threats to child health and has called for urgent government action to ensure that children grow up in safe and healthy environments. Despite this, the majority of children’s home environments are unsafe because of physical punishment. Children’s rights organizations like UNICEF and others have made it clear that physical punishment is an act of violence that infringes on children’s fundamental rights to safety, dignity, and physical well-being. 2 Goal 16.2.3 of the 2030 Agenda for Sustainable Development calls for all forms of violence against children to be eliminated. There is a growing consensus among health professionals that physical punishment is detrimental and ineffective,7–9 leading 62 countries to prohibit physical punishment of children in all settings and a further 27 countries to commit to doing so. 10
Dr. Sendler: 63 percent of children aged 2–4 years are regularly punished by their caregivers in countries where physical punishment is permitted by law; this amounts to 250 million children. It is possible that parents are not receiving or believing the message that physical punishment is both ineffective and potentially harmful to their children’s health and development. Research to date has been summarized in hundreds of specialist studies or detailed meta-analyses5,12–14, which are not easily accessible to health professionals whom parents consult for discipline advice. 15 Furthermore, physical punishment in the home, school, or both is not prohibited in the majority of countries. Legislators may not be aware of the strength of the research evidence against corporal punishment or the likelihood that such legislation would protect children from harm.
It is thus the goal of this narrative review to summarize the past two decades of research on physical punishment in a format that is understandable to policymakers, community leaders, and practitioners. There is a growing movement around the world to legislate against the use of physical punishment, even though psychological punishments like yelling, humiliating or shaming children are also common.
Our review was guided by three strategic decisions. Initially, we focused on studies published in 2002, the year in which the first comprehensive meta-analysis of research into physical punishment was published in the field. Secondly, we only included studies that focused on physical punishment and excluded studies that dealt with more serious assaults on children. As a third step, we only looked at long-term studies in which children were followed prospectively and the initial levels of outcome were taken into account, meeting the minimal criterion for causality that physical punishment must precede the measured outcome in time and addressing concerns about reverse causality.
After a preliminary title screening, the database searches turned up 3855 unique records, of which 2198 were subsequently discarded as duplicates. Web of Science alerts and expert communication led to the discovery of an additional five studies. A total of 68 papers reporting on 69 studies (one article reported on two samples) met the inclusion criteria after being evaluated by two independent reviewers who looked at 1303 abstracts and 359 full texts. These were saved for further investigation (figure).
Many studies in this field are based on the same datasets, such as the Fragile Families and Child Wellbeing Study (FFCWS) and National Longitudinal Survey of Youth (NLSY)—23 of these studies used the FFCWS and eight used NLSY (NLSY). As a result, researchers from eight different countries contributed their findings to this round of research. The inclusion criteria were not met by any studies conducted in any language other than English. The appendix, pages 2–11, lists the characteristics of the studies that were considered for inclusion.
The terminology used by the original researchers is what we use to describe outcome measures. The studies were categorized into nine broad categories: externalizing behaviors (behavioral difficulties that manifest outwardly and refer to acts towards the external environment that violate social norms or are harmful to others, or both),18,19 internalizing behaviors (behaviors that are directed inwards, including symptoms of anxiety and depression, withdrawal, fearfulness, and somatic complaints),18,19 total behavior difficulties (composite measures of both externalizing and internalizing behaviors).18,19 (CPS).
The included research is summarized in the table below. Many studies looked at multiple outcomes, so there were 98 effect sizes in total. Several outcomes were examined multiple times with the same dataset, but each dataset was counted only once per category to ensure the independence of the findings within each outcome category. The majority findings were coded when there were discrepancies between studies from the same dataset. According to one example, out of three studies that examined cognitive abilities using data from the FFCWS, only one concluded that the FFCWS had a detrimental effect, while the other two concluded that it had no significant association. The total number of effect sizes was 64 when each independent dataset was counted once for each outcome.
In 38 separate studies, there was a significant (p0.05) link between worse long-term outcomes and physical punishment (59 percent ). In 15 independent samples, no significant correlations were found (23 percent ). Physical punishment had no proven positive effects on children, according to any of the studies that looked into the topic. Only four subgroups were found to be associated with physical punishment and positive outcomes in all of these investigations, and these findings should be taken with a grain of salt, as they were not found in any of the independent samples examined.
The most studied outcomes were those that resulted in externalizing behavior. Structural equation models, fixed effects models, growth curve models, and propensity score matching were used in 38 of the 55 studies (69 percent). Almost all of the covariates have been taken into account. The broad category of externalizing behaviors was the focus of some studies, while subcategories like aggression were the focus of others.
The Achenbach Child Behavior Checklist 34 was used in 27 studies from 19 independent samples with follow-up periods of up to 12 years to measure externalizing behavior. FFCWS data came into play in five of these studies35–39; ECLS-K data came into play in two; and data from the US Child Development Project came into play in three. 42–44 More than 99% of the research on externalizing behavior was conducted in the United States.
Twenty studies and six different samples examined how aggressive children can be. Most were done in the early years of life. Physical punishment predicted an increase in aggressive behavior over time in five out of six samples. FFCWS data was used in 15 studies, all of which found that physical punishment has detrimental effects on children of all ages, regardless of the method used to analyze the data. 57–71 Four out of the five remaining samples, including those from Canada, Switzerland, the United States, and elsewhere, showed associations with an increase in aggressive behavior. 30,74 Physical punishment and aggressive behavior were found to be unrelated in only one case study. 75
Eight studies with five different samples looked at antisocial behavior and conduct issues. The duration of follow-up ranged from two to twelve years. Two studies23,24 found that physical punishment increased antisocial behavior, while the other two studies found no link between physical punishment and antisocial behavior. 25,26 Physical punishment was linked to increases in antisocial behavior, conduct issues, and symptoms of oppositional defiant disorder in four additional studies involving independent samples.
A total of 15 studies from ten independent samples found that internalizing behavior was the result. Aside from a single study that measured depressive symptoms,77 all studies reported on an overall measure of internalizing behavior symptoms. The data from the FFCWS was used in six studies. 38,39,59,64,66,67 Most studies were conducted in the early stages of childhood, but some followed children into their early adolescent years..
Damian Jacob Markiewicz Sendler: Outcomes included children’s vocabulary, literacy and reading and math skills, readiness for school, school engagement, and learning methods and approaches. The results were wildly inconsistent. Physical punishment was linked to lower cognitive abilities in early childhood, according to two separate studies. 83,84 There was a correlation between physical punishment and lower vocabulary scores only in one of three analyses of FFCWS data that used the same vocabulary test at different ages but with different follow-up periods. 37,67 The results of three studies were mixed, with some cognitive outcomes showing a negative impact but not all. 30–32 There was a correlation between better cognitive performance in middle childhood and adolescence and lower school engagement, according to one study.
At 36 months, physical punishment was associated with lower quality of observed parent–child interaction, and better interaction quality was associated with less physical punishment over time. Cross-lagged path models showed reciprocal associations between the parent–child relationship and physical punishment.
In a study using the National Survey of Child and Adolescent Well-Being, researchers found that peer isolation among young children (such as having no one to talk to at school) was not associated with physical punishment.
No overall correlations between child-reported physical punishment at the age of 14 and self-reported initiation of dating violence were found for the subsample of single mothers who participated in the evaluation. Dating violence was linked to physical punishment by married mothers, but not to physical punishment by married fathers, according to the findings of the study.
Children’s Protective Services (CPS) involvement is typically a sign of suspected child abuse when a family reports CPS involvement. Three studies in the United States looked at the link between physical punishment in early childhood and subsequent CPS involvement for suspected child abuse or neglect.. As a result, we didn’t require that a study control for prior maltreatment or involvement with CPS.
A common belief is that physical punishment is a good way to teach children to behave better. Physical punishment has been shown to lead to an increase in behavioral issues over time, according to the studies we reviewed. Physical punishment has been linked to an increase in child behavior problems, including aggression, in three previous meta-analyses. 5,12,14 As a result, parents’ attempts to improve their children’s behavior with physical punishment have been ineffective, and instead appear to be increasing undesirable behaviors in their children.
Children whose parents used physical punishment were more likely to suffer abuse that led to the involvement of the Child Protective Services (CPS), according to three studies from two separate datasets86–88. According to previous meta-analyses, physical punishment has been linked to an increased risk of maltreatment in children5,12, and a study of Canadian CPS records, which was not included in our narrative review, found that 75% of cases of substantiated physical abuse took place as a result of retaliation. 89 Physical punishment has been linked to an increased risk of abuse. They also challenge the arbitrary distinction between acceptable and unacceptable violence toward children….
Cross-sectional studies of physical punishment have been criticized for not being able to determine whether physical punishment causes behavioral problems, in part because observed correlations could reflect reverse causality—namely, children’s behavior problems eliciting physical punishment. Concerns about whether physical punishment can predict changes in a child’s behavior were addressed by including only prospective longitudinal studies that included a child’s initial levels of behavior in our review.
15 studies in our review used a cross-lagged panel design that simultaneously models both the longitudinal association between physical punishment and child behavior as well as the relationship between initial child behavior and parents’ use of physical punishment at a subsequent wave. After controlling for the fact that physical punishment is more likely to lead to externalizing behavior problems, physical punishment consistently predicted a worsening of these issues over time in the six independent studies and the nine studies that used data from the FFCWS.
Studies using cross-lagged models, on the other hand, found no evidence that internalizing resulted in more physical punishment over the course of time.
For children’s social competence57 and vocabulary scores, no reciprocal effects were found. 67 If a child elicitation effect is not present, it is unlikely that any other outcomes besides externalizing behavior problems are the result of reverse causation.
Damien Sendler: Most studies on physical punishment have been criticized for being non-experimental because assigning children at random to a physical punishment condition would be considered unethical. This means that other possible explanatory factors cannot be ruled out in the studies. 41 But several studies in our review used methods that help us rule out other possible explanations and thus increase our confidence that the findings are consistent with a causal conclusion.
PSM, which matches children on a wide range of individual and family background characteristics, was used in three studies to create quasi-experimental comparisons. The only difference between the children was whether they had experienced physical punishment. Children who were physically punished from the age of 5 to 8 years increased their externalizing behavior significantly more than those who were not physically punished, according to data from the US ECLSK study (12 112 families). 41 There were 29 182 families studied in Japan using PSM to see if children who were physically punished had more behavioral issues over time than those who weren’t. 80 Researchers in Colombia found that young kids who were physically punished were less able to learn cognitively than their peers who weren’t punished. 83 It’s hard to argue with the conclusion that physical punishment is bad for children’s development, especially when three studies using rigorous statistical methods and large samples from three different countries all came to the same conclusion.
Fixed effects regression is a second way to rule out other possible explanations for the association between physical punishment and child outcomes. It uses difference scores for both the predictor and the outcome to control for time invariant unobserved characteristics. This method was used in two of the studies we reviewed. There was a correlation between increased physical punishment and an increase in children’s externalizing behaviors, according to data from the NLSY. 47 Using data from the FFCWS, one researcher found that physical punishment predicted an increase in child aggression. 65
Our review included two studies that used data from randomised controlled trials of interventions that reduced physical punishment; even though physical punishment was not randomly assigned, the experimentally induced reductions in physical punishment predicted improvements in children’s problem behaviors over time.
We found a slew of studies looking into possible differences in the effects of physical punishment on children’s outcomes based on their own or their parents’ characteristics. Among the most frequently cited modifying factors are the child’s gender, race or ethnicity, and parental style.
Studies with four independent samples in the United States found no change in the link between physical punishment and an increase in behavioral issues for children based on their gender.
Damian Sendler
On the one hand, two studies out of the United States found a stronger link between boys and problem behavior than did the Chinese study that looked at the same topic24,69. 20 Children’s gender did not influence the outcome of child aggression or conduct problems, but physical punishment was linked to an increase in prosocial behavior in girls. 72 According to a Greek study, physical punishment led to more boys engaging in externalizing behaviors, while physical punishment led to fewer girls engaging in externalizing or internalizing behaviors. 22 It appears that physical punishment has a negative effect on both boys and girls, but the extent of this effect differs between studies.
According to the cultural normativeness theory, which has been the subject of previous research, the effectiveness of physical punishment may differ depending on the culture of the family administering it.
90 Many of the studies we reviewed tested for the influence of a family’s ethnicity or race on the results. However, in the ECLSK,40,82, the FFCWS,35,70, or five other independent samples, there was no modification in the link to increased externalising behavior. 27,42,52,56,77 Some studies using the NLSY found that racial or ethnicity had an effect on behavioral issues in children26,29, while others found no such effect. 23,24,28
Another study using data from the National Longitudinal Study of Youth (NLSY) found no ethnic or racial differences in achievement in math or reading.
84 In three studies, there was a change, but it was not in the direction cultural normativeness theory predicted. 27,33,50 There was no evidence from the studies conducted in the United States that race or ethnicity has any bearing on the effects of physical punishment on children’s outcomes.
It’s been suggested that parents can mitigate the negative effects of physical punishment by employing a more positive approach to raising their children. Using NLSY data, one study did find a link between responsiveness and behavior problems28, but another study using NLSY data found that neither responsiveness nor cognitive stimulation buffered the link between physical punishment and poorer reading and mathematics abilities.29.30 84 Parental warmth did not mitigate the effects of physical punishment on child behavior, according to three other studies. 60,74,77 There is no evidence that parenting style influences the link between physical punishment and negative outcomes for children..
Consistent and robust evidence shows that physical punishment does not improve child behavior, but rather increases the risk of child maltreatment. As a result, there is no empirical justification for parents to continue to employ physical punishment. Physical punishment is a violation of a child’s right to protection and should be banned by the United Nations Committee on the Rights of the Child. 2
All physical punishment of children has been prohibited in 62 countries around the world, ensuring that children and adults alike are protected by their laws. Across the globe, there are ten in Africa, ten in Central and South America, six in Asia-Pacific, 35 in Europe, and one in the Middle East where these prohibitions are in place. 10 All over the world, they can be found regardless of religion, economic status or political leanings. A ban on all physical punishment of children was also enacted in 2019 and 2020 in Scotland and Wales, two UK constituent countries.
Damian Jacob Sendler
A growing body of evidence suggests that such laws have a significant impact on parents’ attitudes and behavior, resulting in a significant decrease in both parental approval and the prevalence of physical punishment.
92 Sweden, which outlawed all forms of physical punishment for children in 1979, serves as an example of how such a ban can gradually reduce the use of physical punishment. Over the course of 53 years, the percentage of participants who reported being slapped as a child decreased from 83 percent in 1958 to 51 percent in 1981, and then dropped all the way to 27 percent in 2011—a two-thirds drop. 93 It is possible to increase knowledge and change attitudes through public education; however, these efforts are slowed and undermined by the law. For the most effective change in attitudes and use of physical punishment, a study of five European countries found that it occurs when public education and law are consistent. 94,95
Laws that protect children from abuse and neglect do not lead to an increase in the number of caregivers in the criminal justice system. New Zealand’s prohibition was only prosecuted for serious acts (e.g. kicking, holding by the neck, inflicting injuries) and no one was sentenced to prison during the five years following its implementation. To better assist children in need, police began collaborating more closely with child welfare agencies after the prohibition on corporal punishment was passed into law. 96 Since almost every country with a ban has an educational purpose, the goal is to raise awareness and shift attitudes and clarify the role of parents in their caregiving responsibilities rather than to penalize those who break the rules. 92
Communities and institutions can help prevent and reduce physical punishment in addition to national legal bans. For instance, No Hit Zones have been successfully implemented in numerous US locations, especially hospitals.. Forbidding children from being hit by their parents is an effective way to increase the willingness of hospital staff to intervene, as well as parents’ compliance with their staff’s advice not to physically punish their children. 97 There are many low-cost options for implementing No Hit Zones, and they can be used in a wide range of settings and across many communities (eg, schools, libraries, supermarkets). Educating parents and caregivers on disciplinary strategies that emphasize the importance of children’s understanding rather than enforcing compliance, and that are based on their rights to protection and dignity should be a priority for governments, stakeholders, and practitioners.
