The state of research on the effects of physical punishment.

• Author: Smith, Anne B.

Abstract

Long considered an effective, and even necessary, means of socialising children, physical punishment has been revealed to be a predictor of a wide range of negative developmental outcomes. The extent of agreement in the research literature on this issue is unusual in the social sciences. Physical punishment is associated with increased child aggression, antisocial behaviour, lower intellectual achievement, poorer quality of parent--child relationships, mental health problems (such as depression), and diminished moral internalisation. The evidence about whether physical punishment results in short-term compliance is mixed, with some studies showing effectiveness in achieving this and others not. Short-term compliance can, however, be achieved as effectively without using physical punishment. Physical punishment has negative effects on child outcomes, especially if it is harsh, regardless of culture. When punishment use is normative in a culture, the effects are slightly less negative. Research findings support ongoing efforts to help parents use more positive methods of parenting, and the removal of a defence in law for the use of physical punishment against children.

INTRODUCTION

Research findings about the effects of physical punishment on outcomes for children provide a persuasive argument in favour of changing policies on the use of physical punishment within families. (2) A research team from the Children's Issues Centre recently reviewed research on the guidance and discipline of children (Smith et al. 2005). This paper summarises and updates a section of that report. The research suggests that physical punishment is both ineffective and harmful as a method of disciplining children. This paper provides both an overview and specific examples of recent research on physical punishment relating to the following topics: social, cognitive and mental health; moral internalisation and family relationship outcomes; and the interactions with culture and ethnicity. It is firstly important to get some definitions clear, because much of the debate about the effects stems from the difficulty in agreeing on definitions.

THE DIFFERENCE BETWEEN DISCIPLINE AND PHYSICAL PUNISHMENT

Physical or corporal punishment is the use of force to cause pain, but not injury, for the purpose of correction or control (Straus and Stewart 1999). Although researchers attempt to distinguish between physical punishment and abuse, this is very hard to do and there is no general agreement about the dividing line between physical punishment and physical abuse. It is not possible to define what a "safe smack" is. Abusive and non-abusive parents differ mainly in how often and how severely they physically punish their child, and whether that physical punishment is purportedly for correcting children.

Discipline is the guidance of children's moral, emotional and physical development, enabling children to take responsibility for themselves when they are older (Holden 2002, Wissow 2002). It involves teaching children the boundaries of what is acceptable and what is not acceptable, and it makes them aware of the values and actions that are acceptable in their family and society. Discipline can be positive, for example, praising the child for doing something good or for stopping doing something inappropriate; or discipline can be negative, for example, smacking a child for doing something wrong. Positive discipline normally involves helping children to understand why certain behaviour is unacceptable and other behaviour is acceptable. Negative discipline focuses on doing what you are told in order to avoid something unpleasant.

A distinction is often made between "power-assertive" and "inductive" discipline. Power-assertive disciplinary methods involve following a child's inappropriate behaviour with a negative consequence (smacking, threats, withdrawal of privileges) without explanation or justification. Inductive methods involve setting limits, setting up logical consequences, reasoning and explanation (Holden 2002).

METHODOLOGICAL ISSUES

There are methodological problems in determining the effects on children's behaviour of physical punishment and other methods of discipline. It is not possible to assign children randomly to "punishment" and "no punishment" groups, so it is difficult to establish a causal relationship. The other problems are confounding variables (other variables that are associated with punishment and difficult to separate from it), limited outcome measures (e.g. retrospective reports by parents or children), the definition of punishment (and distinguishing it from physical abuse), and lack of generalisability because of limited sample populations (e.g. clinical samples or European-only samples).

Many studies have indicated positive relationships between corporal punishment and various measures of child behaviour, but most of these studies have been cross-sectional and correlational in design. Correlational studies simply show the relationship of two or more variables at a given point in time, and are limited in their ability to demonstrate causality. For example, if a correlation is found between physical punishment and child aggression, it may be that physical punishment leads to child aggression. However, there is an equally plausible argument that the aggressive behaviour may be the causal variable that leads to the parental punishment, i.e. noncompliant children elicit more punishment from their parents. Most researchers, however, think that there is a bidirectional effect, with both variables both causing and being the effect of the other. There are now some longitudinal studies that provide evidence for causality, which will be discussed below.

WHAT IS THE EVIDENCE?

This section summarises the evidence concerning the effects of physical discipline by referring to a major literature review published in 2002 (Gershoff 2002a) and to additional studies.

The research on the effects of corporal punishment achieves a degree of consistency that is rare in social science (Holden 2002, Straus and Stewart 1999). This research shows that there is a variety of negative long-term consequences of using physical punishment as a method of family discipline. Gershoff (2002a) carried out a meta-analysis of 92 studies on corporal punishment, which examined the effect of punishment on 11 outcome variables. Gershoff's review specifically excluded studies that included abusive or potentially abusive techniques in their definition of corporal punishment.

Gershoff (2002a) found that corporal punishment was only associated with one desirable behaviour, and this was immediate compliance. However, the study findings were inconsistent, with two of the five studies showing that corporal punishment was associated with less compliance. The other three studies were of clinical samples of children who had been referred for problem behaviours. Hence, the generalisability of their findings is doubtful and suggests that corporal punishment may only be effective for disobedient and disruptive children. Gershoff points out that most parents are not only interested in immediate compliance, but also want ongoing compliance, and the research shows that this does not necessarily take place and that there are other unforeseen long-term consequences of corporal punishment.

Gershoff's (2002a) review and meta-analysis of the research literature on corporal punishment provides the following summary:

Ten of the 11 meta-analyses indicate parental corporal punishment is associated with the following undesirable behaviours and experiences: decreased moral internalisation, increased child aggression, increased child delinquent and antisocial behaviour, decreased quality of relationship between parent and child, decreased child mental health, increased risk of being a victim of physical abuse, increased adult aggression, increased adult criminal and antisocial behaviour, decreased adult mental health, and increased risk of abusing own child or spouse. Corporal punishment was associated with only one desirable behaviour, namely, increased immediate compliance. (Gershoff 2002a:544) In part because of the methodological problems with studies of corporal punishment, advocates of corporal punishment have dismissed many of these negative findings (Larzelere...