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    Clinical Child and Family Psychology Review, Vol. 8, No. 1, March 2005 ( C2005)

    DOI: 10.1007/s10567-005-2340-z

    Comparing Child Outcomes of Physical Punishment and

    Alternative Disciplinary Tactics: A Meta-Analysis

    Robert E. Larzelere1,2 and Brett R. Kuhn1

    This meta-analysis investigates differences between the effect sizes of physical punishmentand alternative disciplinary tactics for child outcomes in 26 qualifying studies. Analyzingdifferences in effect sizes reduces systematic biases and emphasizes direct comparisons be-tween the disciplinary tactics that parents have to select among. The results indicated thateffect sizes significantly favored conditionalspanking over 10 of 13 alternative disciplinary

    tactics for reducing child noncompliance or antisocial behavior. Customary physical punish-ment yielded effect sizes equal to alternative tactics, except for one large study favoring phys-ical punishment. Only overly severe or predominant use of physical punishment comparedunfavorably with alternative disciplinary tactics. The discussion highlights the need for betterdiscriminations between effective and counterproductive use of disciplinary punishment ingeneral.

    KEY WORDS: children; parenting; discipline; punishment; spanking.

    Uncertainty about the effects of physical pun-ishment on children has persisted despite decadesof research. Two major perspectives have emergedrecently. The first is an unconditional anti-spanking

    perspective, advanced by both social scientists(Gershoff, 2002; Straus, 2001) and advocacy groups(EPOCH-Worldwide, 2004). In response, at least 13countries have passed laws banning all physical pun-ishment by parents (EPOCH-Worldwide, 2004).

    The second perspective, which has been calledthe conditional-spanking perspective (Benjet &Kazdin, 2003), has attempted to identify condi-tions under which spanking may be beneficial or atleast not detrimental to children. The conditional-spanking perspective emphasizes the parenting con-text and manner of implementation, which may

    distinguish effective from counterproductive usesof punishment more than its form (e.g., physicalor nonphysical). In one sense the disciplinary ac-

    1Psychology Department, Munroe-Meyer Institute, University of

    Nebraska Medical Center, Nebraska.2Address all correspondence to Robert E. Larzelere, Psychology

    Department, MMI, 985450 Nebraska Medical Center, Omaha,Nebraska 68198-5450; e-mail: [email protected].

    tions of parents in most cultures have reflected aconditional-spanking perspective until recently. In19941995, for example, 94% of American parentsand 52% of Canadian parents of 3- and 4-year-olds

    reported using physical punishment at least occasion-ally (Larzelere, 2004; Straus & Stewart, 1999). Theconditional-spanking perspective holds that spank-ing should be investigated under the conditions forwhich parents have considered it advisable beforeimposing a spanking ban on parents (Bauman &Friedman, 1998; Baumrind, Larzelere, & Cowan,2002; Eysenck, 1993; Friedman & Schonberg, 1996b;Larzelere, Baumrind, & Polite, 1998).

    Two recent literature reviews from these twoperspectives did little to resolve the issue. Gershoffs(2002) meta-analysis concluded that physical pun-

    ishment was linked positively to immediate com-pliance, but negatively with 10 other outcomesin children and families. In a qualitative review,Larzelere (2000) concluded that causal evidenceshowed that nonabusive spanking of 26-year-oldsproduced more beneficial than detrimental child out-comes when it was used to enforce milder disci-plinary tactics such as reasoning or time-out, es-pecially in subcultural groups that support its use.

    1

    1096-4037/05/0300-0001/0 C 2005 Springer Science+Business Media, Inc.

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    2 Larzelere and Kuhn

    Benjet and Kazdin (2003) recently compared thetwo reviews and concluded, A top priority for re-search on spanking would seem to be a comparisonof spanking with alternative procedures that alreadyhave considerable evidence in their behalf (p. 215).The current meta-analysis attempts to address thispriority by investigating the studies included in eitherreview that examined one or more alternative dis-ciplinary tactics in addition to physical punishment.It also investigates several methodological problemsthat could explain the discrepant conclusions fromthe two reviews (Benjet & Kazdin, 2003).

    To provide a context for this meta-analysis, webriefly summarize the methodological problems thathave hindered definitive conclusions about physicalpunishment. We then clarify why a meta-analysisusing differences in effect sizes between physicalpunishment and disciplinary alternatives can reduce

    these methodological problems.

    Methodological Issues

    The spanking controversy persists largely be-cause pervasive methodological problems have per-mitted a wide range of interpretations. These prob-lems include predominantly correlational research;failing to discriminate among nonabusive, customary,and overly severe use of physical punishment; mea-suring disciplinary practices and child outcomes fromthe same information source; and failing to rule out

    plausible alternative explanations.The strongest evidence against physical punish-

    ment in Gershoffs (2002) thorough meta-analysisconsisted of longitudinal correlations, i.e., zero-ordercorrelations between physical punishment and sub-sequent child outcomes. Although such correlationsare consistent with a causal effect (Smith, 2002),their pattern is typical of most corrective interven-tions (Larzelere, Kuhn, & Johnson, 2004). In post-treatment comparisons, recipients of corrective inter-ventions will compare poorly to those not needingsuch interventions, whether the intervention is deliv-

    ered by physicians (e.g., radiation treatment), educa-tors (Head Start), psychologists (marital counseling),or parents (punishment).

    Consider radiation treatment as an example. Pa-tients who received radiation treatment last year aremore likely to experience cancer-related symptomsthis year than those who did not receive (or need)radiation treatment. Longitudinal zero-order corre-lations would indicate that radiation treatment is

    associated with increased cancer-related symptoms.Of course, the initial presenting problem (cancer)is the causal factor underlying that correlation be-cause it leads to both the corrective intervention(radiation treatment) and the subsequent outcome(cancer). Consequently, zero-order longitudinal cor-relations cannot discriminate effective corrective in-terventions from those that are counterproductive.

    Second, most of the research on physical pun-ishment lumps together nonabusive and custom-ary punishment with overly severe forms of physi-cal punishment. For example, 65% of the studies inGershoffs (2002) meta-analysis included overly se-vere physical punishment in their measure, accord-ing to Baumrind et al. (2002). Examples ranged fromvaguely defined punitive discipline (6% of thestudies), composite measures of the frequency andseverity of physical punishment (29%), and the in-

    clusion of extreme violence (31%), such as slappingin the face (seven studies), beating up (three studies),or hitting with a fist and causing bruises and cuts (onestudy).

    Third, many studies of disciplinary tactics havebased the antecedent and consequent variables onthe same source of information. Typically, moth-ers reported both their disciplinary tactics and theirchilds behavior. In retrospective studies, grown chil-dren reported both their current functioning and thedisciplinary tactics they received earlier in life. Thissame-source bias has been shown to inflate associ-ations between disciplinary tactics and adverse out-

    comes (Yarrow, Campbell, & Burton, 1968).Finally, plausible alternative explanations of the

    data on physical punishment have not been ruledout, resulting in widely discrepant explanations forthe varied outcomes across studies. Consider thestrongest evidence of the effectiveness of spanking.Four small-randomized clinical studies found thatspanking was effective in reducing defiance in clin-ically oppositional 26-year-olds (Bean & Roberts,1981; Roberts; Day & Roberts, 1983; Roberts, 1988;Roberts & Powers, 1990). The difference in effectsizes between those four randomized studies (mean

    d = 1.21) and the 113 non-randomized studies (meand = .35) in Gershoff (2002) approached the largestdifference ever found in a meta-analysis (Lipsey &Wilson, 1993). This difference could be explained byone or more of the following confounded interpre-tations. Compared to the non-randomized studies,Roberts four randomized studies (1) had causallystronger evidence, (2) limited spanking to two open-handed swats under the supervision of a clinical

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    Physical Punishment vs. Alternative Tactics 3

    psychologist, (3) used spanking only to enforce com-pliance with time-out, (4) applied only to childrenfrom 2 to 6 years of age who (5) were clinically re-ferred for oppositional behavior problems, and (6)focused on decreases in defiance in the clinic as theprimary outcome. Whereas advocates of the anti-spanking viewpoint consider the type of outcome(short-term compliance) to be the crucial distinction(Gershoff, 2002; Straus, 2001), conditional-spankingresearchers emphasize the stronger causal evidence,the specific conditions in the randomized studies(e.g., the childs age, the discipline situation), and theway in which spanking was implemented (Baumrindet al., 2002; Larzelere, 2000).

    Although these four methodological problemsare often acknowledged, the extent to which theyundermine research conclusions has received insuf-ficient attention. Suppose radiation treatment were

    studied in the same way that researchers have investi-gated physical punishment. Borrowing statistics fromGershoffs (2002) thorough meta-analysis, two-thirds(65%) of studies of radiation treatment would haveincluded excessive dosages of radiation (Baumrind etal., 2002), 58% would have been cross-sectional stud-ies, and only 4% would have taken into considera-tion the presence or severity of cancer. Would it besurprising that patients who received radiation treat-ment last year had higher rates of cancer both lastyear and this year, compared to those who did notreceive (or need) radiation? A meta-analysis of ra-diation treatment using predominantly correlational

    studies would come to the same conclusions as Ger-shoffs (2002) meta-analysis, specifically that radia-tion treatment is consistently linked to detrimentaloutcomes. As aptly noted by Straus (2001), validcausal conclusions require controlling for the effectsof initial child misbehavior. Otherwise, initial childmisbehavior may lead to more disciplinary tactics aswell as worse child outcomes, which would accountfor the associations found by Gershoff (2002).

    Rationale for a Meta-Analysis

    of Differential Effect Sizes

    This meta-analysis attempts to reduce these per-vasive methodological problems by (1) distinguishingamong four types of physical punishment, (2) basingeffect sizes on each studys strongest methodologicalevidence whenever possible, and (3) analyzing differ-ential effect sizes between physical punishment andalternative disciplinary tactics.

    To address the lumping problem, we distin-guish among conditional spanking, customary phys-ical punishment, overly severe physical punishment,and predominant use of physical punishment. Con-ditional spanking (as labeled by Benjet & Kazdin,2003) refers to spanking under the limited condi-tions that have been associated with better child out-comes (e.g., spanking when a 26-year-old refuses tocomply with time out). The purpose of distinguish-ing this category is to determine whether spankingis associated with better outcomes than alternativetactics even under ideal conditions. Customary phys-ical punishment represents the manner in which par-ents typically use physical punishment. The purposeof this category is to investigate whether typical useof physical punishment is associated with better orworse outcomes than alternative tactics. Overly se-vere physical punishment includes the use of exces-

    sive force, hitting with an object, or slapping in theface (Baumrind et al., 2002). Finally, predominantus-age indicates that physical punishment is the parentsprimary disciplinary method, i.e., it is preferred overmilder disciplinary tactics.

    This meta-analysis bases effect sizes on thefindings from each study that are methodologicallystrongest. For example, our effect sizes are basedon results that take initial child misbehavior into ac-count from distinct sources of information, when-ever possible. This choice contrasts with Gershoffs(2002) decision to base effect sizes on correlationsfor the sake of consistency, ignoring methodologi-

    cally stronger findings in several studies.Finally, this meta-analysis estimates differences

    in the effect sizes of physical punishment vs. alter-native disciplinary tactics, using identical methodswithin the same study. If the apparently detrimen-tal child outcomes reflect causal effects unique tophysical punishment, then the effect sizes of physi-cal punishment should compare poorly to the effectsizes of alternative disciplinary tactics. On the otherhand, if detrimental child correlates of physical pun-ishment represent methodological artifacts, then theeffect sizes of alternative disciplinary tactics should

    appear equally detrimental.A methodology for analyzing differences be-tween effect sizes is already well established for ran-domized studies. It is based on the differential ef-fect size contrasting post-treatment outcomes from atreatment and a control group. For the usual effectsize measure (d), this is the same as calculating aneffect size for each group (e.g., improvement frompre-to-post) and then using the difference between

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    4 Larzelere and Kuhn

    those two effect sizes. This equality is based on twoassumptions. First, the treatment and control groupmust have identical pre-treatment scores, which ran-domization guarantees in the long run.3 The secondassumption is that the effect sizes for the treatmentand control groups are based on the same stan-dard deviation. When these assumptions apply, typi-cal meta-analyses of randomized clinical trials can beconsidered equivalent to analyses of differences be-tween effect sizes. The only distinction in our meta-analysis is that it compares two treatments (disci-plinary tactics) with each other rather than treatmentand control groups.

    The major advantage of analyzing differencesbetween effect sizes, however, is for non-randomizedstudies, which dominate this literature. Causal con-clusions can be supported from correlational stud-ies only to the extent that plausible alternative in-

    terpretations have been ruled out (Larzelere et al.,2004; Shadish, Cook, & Campbell, 2002). This prin-ciple applies to individual studies as well as to meta-analyses. For example, an alternative explanation forthe positive correlation between physical punishmentand subsequent antisocial behavior is that the childsinitial antisocial behavior may increase both the fre-quency of physical punishment and subsequent an-tisocial behavior. Just as individual studies controlfor this possibility by using initial child misbehavioras a covariate, this meta-analysis uses differences be-tween effect sizes to control for initial child misbe-havior.

    A second advantage of analyzing differences be-tween effect sizes is that they allow researchers todirectly compare realistic disciplinary choices. Bas-ing effect sizes on simple associations between a dis-ciplinary tactic and a child outcome implicitly com-pares parents who use that disciplinary tactic withthose who do not use it. Instead of choosing betweena given disciplinary tactic and doing nothing, parentstypically choose between two or more alternative dis-ciplinary responses (Ritchie, 1999). Differences in ef-fect sizes are better suited for such comparisons.

    In summary, this meta-analysis uses differences

    between effect sizes to control for confounds thatinfluence all disciplinary tactics, e.g., selection biasdue to initial child misbehavior. It falls short of be-ing causally definitive, however, because it rules outonly some plausible interpretations of the underly-ing empirical evidence. This strategy is a substantial

    3When pre-test scores differ, relative pre-post gains provide afairer comparison than post-treatment differences.

    improvement over typical meta-analytic methods forcorrelational data because it controls for importantconfounds and rules out alternative interpretationsassociated with them. At the very least, the cur-rent meta-analysis can determine whether the corre-lationally based effect sizes are uniquely detrimen-tal for physical punishment, are more detrimental forsome disciplinary tactics than others, or are equallydetrimental for all disciplinary tactics. Making thesedistinctions is a crucial step toward designing morecausally informative studies in the future. The re-sults also have important implications for how phys-ical punishment should be used, if at all, and whichalternative disciplinary tactics might be used instead.

    METHOD

    Literature Selection

    Research studies were selected for this meta-analysis from recent reviews by Gershoff (2002) andLarzelere (2000). Both reviews attempted to be ex-haustive within their inclusion criteria for at leastthe previous 26 years. Additional selection criteriainclude the following: (1) The study must have inves-tigated one or more recommended alternative dis-ciplinary tactics as well as physical punishment, us-ing similar research methods. (2) The children hadto average less than 13 years old at the time of thediscipline. Most retrospective studies were excluded

    because they pertained to physical punishment ofteenagers, based on the finding that retrospective re-ports of physical punishment correlated most highlywith mothers reported physical punishment at 1214 years old (Stattin, Janson, Klackenberg-Larsson,& Magnusson, 1995). To be included, retrospectivesurveys had to ask specifically for disciplinary tacticsat a younger age. (3) Selected studies had to inves-tigate at least one child outcome, excluding studiesthat investigated only parental outcomes.

    These criteria yielded 26 studies that investi-gated physical punishment and one or more al-

    ternative tactics, summarized in Table I. Onlyeight of these studies were included in both previ-ous reviews. Eleven studies from Gershoffs (2002)meta-analysis were excluded from Larzeleres (2000)review because they were cross-sectional (sevenstudies) or used overly broad measures of punish-ment (three studies). One other study was incorrectlyexcluded from Larzeleres (2000) review, because itdid specify a younger age in its retrospective survey

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    Physical Punishment vs. Alternative Tactics 5

    TableI.EffectSizesofPhysicalPu

    nishmentandAlternativeDisciplinaryResponsesonChildOutcomesBasisofeffects

    ize&

    Age,Gender

    Discipline

    Effect

    discrepanciesfrom

    Study

    (Parent)a

    Sample

    N

    tacticb

    Outcome

    sizec(d)

    Gershoff(2002)

    Short-termcompliance

    RandomizedClinicalTrials

    BeanandRoberts

    (1981)

    26B,G(M)

    Clinic-referredfor

    disruptivebehavior

    problems

    8

    2-swatspankback-up

    fortime-out(TO;

    conditionalphysical

    punishment[PP])

    Observedcompliance

    rateto30paren

    tal

    commands

    2.80d

    Gainfrompre-testtopost-testmeans.

    Gershoffcomparedpos

    t-testmeansfor

    thecompleteparenttra

    iningprocedure

    vs.ano-treatmentcontrolgroup

    8

    Child-determined

    releasefrom

    time-out(TO)

    Compliance

    1.07

    Gainfrompre-topost-test

    8

    2-swatspankback-up

    fortime-out(TO;

    conditionalPP)

    Time-outsuccess

    (Time-outsrequired

    during30

    commands)

    1.61

    Numberoftime-outsneededcompared

    tothechild-determined

    releasefrom

    time-out.Outcomenot

    inGershoff

    DayandRoberts

    (1983)

    25B,G(M)

    Clinic-referredfor

    disruptivebehavior

    problems

    8

    2-swatspankback-up

    fortime-out(TO;

    conditionalPP)

    Compliancerateto30

    parentalcommands

    3.45d

    Gainfrompre-testtopost-test.Gershoff

    comparedthepost-testsforthespank

    vs.thebarrierback-ups

    8

    Barrier(roomTO)

    back-upfor

    time-out(TO)

    Compliance

    3.51

    Gainfrompre-topost-test

    Roberts(1988)

    2-6B,G(M)

    Clinic-referredfor

    behaviorproblems

    9

    2-swatspankback-up

    forTO(conditional

    PP)

    Compliancerateto

    30+

    parental

    commands

    1.60d

    Gainfrompre-testtopost-test.Studynot

    inGershoff

    9

    Barrier(roomTO)

    back-upforTO

    Compliance

    1.45

    Gainfrompre-topost-test

    9

    2-swatspankback-up

    forTO(conditional

    PP)

    Numberoftime-o

    uts

    (TOs)andTO

    escapespriorto

    complianceto1

    0

    commands

    .13

    MeannumberofTOsand

    TOescapes

    comparedtothebarrierback-up

    RobertsandPowers

    (1990)

    26B,G(M)

    Clinic-referredfor

    behaviorproblems

    9

    2-swatspankback-up

    forTO(conditional

    PP)

    Complianceratetoup

    to60parental

    commands

    1.34c

    Gainfrompre-testtopost-test.Gershoff

    comparedthespankpo

    st-testvs.the

    other3back-upscombined

    9

    Barrier(roomTO)

    back-upforTO

    Compliance

    2.17

    Gainfrompre-topost-test

    9

    Restraintback-upfor

    TO

    Compliance

    1.15

    Same

    9

    Child-determinedTO

    release

    Compliance

    1.52

    Same

    9

    2-swatspankback-up

    forTO(conditional

    PP)

    TOsuccess(children

    withoutexcessive

    TOsorexcessiv

    e

    TOescapes)

    .44

    Proportionofchildrenwithsuccessful

    TOcompliance,comparedto

    child-determinedTOre

    leasegroup.

    OutcomenotusedbyG

    ershoff

    9

    Barrierback-upfor

    TO

    TOsuccess

    1.02

    Same

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    6 Larzelere and Kuhn

    TableI.Continued

    Basisofeffectsize&

    Age,Gender

    Discipline

    Effect

    discrepanciesfrom

    Study

    (Parent)a

    Sample

    N

    tacticb

    Outcome

    sizec(d)

    Gershoff(2002)

    9

    Restraintback-upfor

    TO

    TOsuccess

    .22

    Same

    Within-subjectsequentialanalyses

    Larzelereetal.(1996)

    23B,G(M)

    Volunteers

    38

    Slaphandorspank,

    whetherreasoning

    wasalsousedornot

    (customaryPP,

    contrastedwith

    nexttwotactics)

    Delayuntilnext

    recurrenceof

    disobedience,

    comparedtotypical

    delaysforthatchild

    .05

    Deviationsfromparticipa

    ntsmean

    delays,comparedwithother(i.e.,no

    punishmentorreasonin

    g).Couldnot

    replicateGershoff

    Reasoning,whether

    usedwithphysical

    ornonphysical

    punishmentornot

    Delayuntil

    disobedience

    recurrence

    .01

    Same

    Nonphysical

    punishment

    (time-outor

    privilegeremoval),

    whetherusedwith

    reasoningorPPor

    not

    Delayuntil

    disobedience

    recurrence

    .02

    Same

    Reasoning&PP(no

    nonphysical

    punishment;

    conditionalPP

    combinedthiswith

    Reasoning&PP&

    nonphysical

    punishment)

    Delayuntil

    disobedience

    recurrence

    .02

    Same

    Reasoning&

    nonphysical

    punishment&PP

    (partofconditional

    PP)

    Delayuntil

    disobedience

    recurrence

    .17

    Same

    Reasoningalone(no

    physicalor

    nonphysical

    punishment)

    Delayuntil

    disobedience

    recurrence

    .06

    Same

    Nonphysical

    punishmentalone

    (time-outor

    privilegeremoval;

    noreasoningorPP)

    Delayuntil

    disobedience

    recurrence

    .02

    Same

    Reasoning&

    nonphysical

    punishment(noPP)

    Delayuntil

    disobedience

    recurrence

    .08

    Same

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    Physical Punishment vs. Alternative Tactics 7

    Ritchie(1999)

    3B,G(M)

    Volunteersfrom

    birthrecords

    90

    Spank(conditional

    PP)

    Immediatered

    uction

    inprobabilityof

    defiance

    .97

    Fromimmediatelypriorp

    robabilityof

    defiancecomparedtoimmediately

    subsequentprobability

    ofdefiance.

    StudynotinGershoff

    Reasonoroffer

    alternatives

    Dropindefiance

    .02

    Same

    Threatenorverbal

    powerassertion

    Dropindefiance

    .08

    Same

    Privilegeremoval

    Dropindefiance

    .33

    Same

    Time-out

    Dropindefiance

    .60

    Same

    Noresponse(ignore)

    Dropindefiance

    .02

    Same

    Physicalpower

    assertion

    Dropindefiance

    .45

    Same

    Spank(customaryPP)

    Immediatered

    uction

    inphysical

    or

    passive

    noncompliance

    .07

    Fromimmediatelypriorp

    robabilityof

    twononcompliancetyp

    escomparedto

    theirimmediatelysubsequent

    probability

    Reasonoroffer

    alternatives

    Reductionin

    noncompliance

    .18

    Same

    Threatenorverbal

    powerassertion

    Reductionin

    noncompliance

    .02

    Same

    Privilegeremoval

    Reductionin

    noncompliance

    .24

    Same

    Time-out

    Reductionin

    noncompliance

    .16

    Same

    Noresponse(ignore)

    Reductionin

    noncompliance

    .33

    Same

    Physicalpower

    assertion

    Reductionin

    noncompliance

    .20

    Same

    Correlationalsequentialana

    lyses

    Chapmanand

    Zahn-Waxler(1982)

    1029mos.,B,

    G(M)

    Volunteers

    24

    Physicalcoercion(PP

    orrestraint)

    withoutreasoning

    (customaryPP)

    Immediatecom

    pliance

    .09

    Comparedtotheoverallcompliance

    rate.CouldnotreplicateGershoff

    Physicalcoercion&

    reasoning

    (conditionalPP)

    Immediatecom

    pliance

    .02

    Comparedtotheoverallcompliancerate

    Reasoning(withor

    withoutverbal

    prohibition)

    Immediatecom

    pliance

    .22

    Same

    Verbalprohibition

    Immediatecom

    pliance

    .15

    Same

    Lovewithdrawal

    (includingignoring

    andtime-out)plus

    anyofabovetactics

    Immediatecom

    pliance

    .40

    Same

    Minton,Kagan,and

    Levine(1971)

    27mos.B,G

    (M)

    Volunteers

    70

    PPasproportionof

    observed

    misbehavior

    (predominantPP)

    Disobedience

    requiringma

    ternal

    reprimand

    .55

    Averagedcorrelationsforboysandgirls.

    SameasGershoff

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    8 Larzelere and Kuhn

    TableI.Continued

    Basisofeffectsize&

    Age,Gender

    Discipline

    Effect

    discrepanciesfrom

    Study

    (Parent)a

    Sample

    N

    tacticb

    Outcome

    sizec(d)

    Gershoff(2

    002)

    Explanationsof

    reprimandsas

    proportionof

    misbehavior

    Observed

    disobedience

    .44

    Averagedcorrelationsforboysandgirls

    Antisocialbehavior

    Statisticallycontrolledlongitudinalstudies

    LarzelereandSmith

    (2000)

    6

    9atT1,811at

    T2,B,G(M)

    Nationalsampleof

    youngmothers

    7

    85Frequencyspankedin

    pastweek

    (customaryPP)

    Antisocialbeha

    vior2

    yearslater

    .23

    Meanantisocialfor1or

    moretimesper

    weekvs.nouseofthe

    disciplinary

    tactic,controllingforexternalizing

    problemsatTime1,fiveother

    variablesand6interactionsofthese

    variableswiththedisc

    iplinarytactic.

    Unpublished,notinG

    ershoff

    7

    85Frequencyprivileges

    removedinpast

    week

    Antisocialbeha

    vior

    later

    .21

    Same

    7

    85Frequencygrounded

    inpastweek

    Antisocialbeha

    vior

    later

    .20

    Same

    7

    71Frequencyallowance

    removedinpast

    week

    Antisocialbeha

    vior

    later

    .10

    Same

    7

    85Frequencysentto

    roominpastweek

    Antisocialbeha

    vior

    later

    .18

    Same

    Larzelereetal.

    (1998)

    2

    3atT1,4at

    T2;B,G(M)

    Volunteers

    3

    8

    Slaphandorspank

    (PP)without

    reasoning,as

    proportionof

    misbehavior

    incidents(averaged

    withReasoning&

    PPforpredominant

    PP)

    Disruptivebehavior

    20monthslater

    .41

    Meanpartialcorrelation

    ofproportional

    usagewithsubsequentdisruptive

    behavior,controllingforinitial

    disruptivebehavior.N

    otinGershoff

    (multiplereportsfrom

    samestudy)

    Reasoning&PP

    (proportionaluse;

    partof

    predominantPP)

    Disruptivebehavior

    20monthslater

    .32

    Same

    ReasoningwithoutPP

    ornonphysical

    punishment

    Disruptivebehavior

    later

    .80

    Same

    Nonphysical

    punishment

    (time-outor

    privilegeremoval)

    Disruptivebehavior

    later

    .20

    Same

    Reasoning&

    nonphysical

    punishment

    Disruptivebehavior

    later

    .10

    Same

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    Physical Punishment vs. Alternative Tactics 9

    Within-subjectsequentialan

    alyses

    Larzelereetal.

    (1996)

    23B,G(M)

    Volunteers

    38

    Slaphandorspank

    (PP),whether

    reasoningwasalso

    usedornot

    (customaryPP,

    contrastedwith

    nexttwotactics)

    Delayuntilnext

    recurrence

    of

    fighting,compared

    totypicaldelaysfor

    thatchild

    .08

    Deviationsfromparticipantsmean

    delays,comparedwith

    other(i.e.,no

    punishmentorreasoning).Gershoff

    didnotincludethisoutcome

    Reasoning,whether

    usedwithphysical

    ornonphysical

    punishmentornot

    Delayuntilfighting

    recurrence

    .01

    Same

    Nonphysical

    punishment

    (time-outor

    privilegeremoval),

    whetherusedwith

    reasoningorPPor

    not

    Delayuntilfighting

    recurrence

    .36

    Same

    Reasoning&PP(no

    nonphysical

    punishment;

    (conditionalPP

    combinedthiswith

    Reasoning&PP&

    nonphysical

    punishment)

    Delayuntilfighting

    recurrence

    (deviation)

    .07

    Same

    Reasoning&

    nonphysical

    punishment&PP

    (partofconditional

    PP)

    Delayuntilfighting

    recurrence

    .81

    Same

    Reasoningalone(no

    physicalor

    nonphysical

    punishment)

    Delayuntilfighting

    recurrence

    .09

    Same

    Nonphysical

    punishmentalone

    (time-outor

    privilegeremoval;

    noreasoningorPP)

    Delayuntilfighting

    recurrence

    .26

    Same

    Reasoning&

    nonphysical

    punishment(noPP)

    Delayuntilfighting

    recurrence

    .63

    Same

    Uncontrolledlongitudinalstudies

    McClellandand

    Pilon(1983)

    5atT1,31atT2;

    B,G(M)

    Kindergartensample

    78

    ExtentofPP,

    combining

    frequencyand

    severity(severePP)

    NeedforPow

    er26

    yearslater

    .42

    Meanofcorrelationswith

    Needfor

    Powerformalesandfe

    males.Study

    notinGershoff

    Reasoning

    NeedforPow

    er

    .00

    Non-significa

    ntr

    Privilegeremoval

    NeedforPow

    er

    .00

    Non-significa

    ntr

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    10 Larzelere and Kuhn

    TableI.Continued

    Basisofeffectsize&

    Age,Gender

    Discipline

    Effect

    discrepanciesfrom

    Study

    (Parent)a

    Sample

    N

    tacticb

    Outcom

    e

    sizec(d)

    Gershoff(

    2002)

    Lovewithdrawal

    NeedforPower

    .00

    Non-signifi

    cantr

    Sears(1961)

    5

    atT1,12atT2;

    B,G(M)

    Kindergartensample1

    60

    ExtentofPP,

    combiningseverity

    andfrequency

    (severePP)

    Antisocialagg

    ression

    7yearslater

    .14

    Correlationswithantisocialaggression7

    yearslater.Gershoff

    averaged6

    correlations(cross-se

    ctionalandwith

    prosocial,ambiguous,andantisocial

    aggression)

    Privilegeremoval

    Antisocialagg

    ression

    .12

    Correlationswithlater

    antisocial

    aggression

    Lovewithdrawal

    Antisocialagg

    ression

    .11

    Same

    Yarrowetal.(1968)

    4

    B,G(M)

    Nurseryschoolsample5

    8

    Useofphysical

    punishmentfor

    vignettesabout

    extreme

    disobedience

    (conditionalPP)

    Teacher-rated

    aggressionin

    nurseryschool2

    monthslater

    .38

    Correlation.Gershoffu

    sedthe

    correlationofseverit

    yofall

    punishmentforaggressionwith

    concurrentaggressiontowardparents

    (mother-report)

    Useofreasoningfrom

    vignettes

    Laterschool

    aggression

    .28

    Correlation

    Useofscoldingfrom

    vignettes

    Laterschool

    aggression

    .24

    Same

    Useofprivilege

    removalfrom

    vignettes

    Laterschool

    aggression

    .38

    Same

    Useofisolationfrom

    vignettes

    Laterschool

    aggression

    .18

    Same

    Useofdivertingfrom

    vignettes

    Laterschool

    aggression

    .47

    Same

    Useoflove

    withdrawalfrom

    vignettes

    Laterschool

    aggression

    .24

    Same

    Retrospectivestudies

    Watson(1989)

    0

    5atT1;17at

    T2;B,G(M,

    F)

    NationalMerit

    Scholarshipfinalists

    &average

    test-takers

    2

    500Parent-reported

    spankingand

    possiblytimeout

    beforeage6,

    (customaryPP)

    Youth-reporte

    d

    hostility&m

    ilder

    (obloquial)

    problems

    .09

    Correlationswithhostilityandobloquial

    problems,using.00fornon-significant

    rs.Gershoffusedonlythesignificantr

    withonehostilityme

    asure

    Privilegeremovaland

    assigningextra

    dutiesbeforeage6

    Hostilityandmilder

    behaviorproblems

    .13

    Correlationswithhostility&obloquial

    problems,using.00fornon-significant

    rs

    Uncontrolledcross-sectionalstudies

    Strausand

    Mouradian(1998)

    2

    14B,G(M)

    Randomsampleof

    twocounties

    7

    44

    Howoftenspanked,

    slappedorhitthe

    childduringthe

    past6months,

    controllingfor

    severe

    out-of-controlPP

    ( c o n d i t i o n a l P P )

    Antisocialand

    impulsivebehavior

    .14

    F-valuesforPP,controllingforsevere

    PP,3otherdisciplina

    rytactics,4other

    variables,andtheirinteractionswith

    PP.Gershoffprobablyusedgraphed

    meanantisocialscores,whichcouldnot

    becomparedwithalternativetactics

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    Physical Punishment vs. Alternative Tactics 11

    Percentageof

    spankingsinwhich

    motherssaidthey

    lostitdueto

    anger(severePP)

    Antisocialan

    d

    impulsivebehavior

    .28

    F-valuesforseverePP,w

    ithabove

    controls

    Howoftentheyused

    disciplinary

    reasoning,privilege

    removal,and

    time-outduring

    past6months

    Antisocialan

    d

    impulsivebehavior

    .39

    F-valuesforthesealternativedisciplinary

    tactics,withabovecon

    trols

    Substanceabuse

    Retrospectivestudies

    Tennantetal.(1975)

    014atT1,M=

    23atT2;B

    (M,F)

    USArmysoldiers

    5044

    Spanking(customary

    PP)

    Frequentuse

    of

    hashish,alcohol,

    amphetam

    ines,and

    opiates

    .24

    Percentageofmostandleastfrequent

    usersreportingbeings

    panked.

    Averagedacross4substances.Not

    amongGershoffs11o

    utcomes

    Non-contact

    punishment

    Frequentuse

    of

    hashish,alcohol,

    amphetam

    ines,and

    opiates

    .08

    Percentageofmostvs.le

    astfrequent

    usersreportingreceivingthis

    punishment.Averaged

    across4

    substances

    Watson(1989)

    05atTime1;17

    atTime2.B,

    G(B)

    NationalMerit

    Scholarshipfinalists

    &average

    test-takers

    2500

    Parentalreportof

    spankingand

    possiblytimeout

    beforeage6

    (customaryPP)

    Youth-repor

    ted

    alcoholusage

    .02

    Correlation.Outcomeno

    tinGershoff

    Withdrawalof

    privilegesand

    assigningextra

    dutiesbeforeage6

    Youth-repor

    ted

    alcoholusage

    .10

    Correlatio

    n

    Conscience&resistancetote

    mptation

    Uncontrolledlongitudinalstudies

    Grinder(1962)

    56atT1,1112

    atT2;B,G

    (M)

    Kindergartensample

    140

    ExtentofPP,

    combiningseverity

    andfrequency

    (severePP)

    Resiststemp

    tationin

    forbidden-toylab

    test6yearslater

    .24

    Thepercentageofchildrenwhoresisted

    temptationforhighvs.lowuseofthe

    disciplinarytactic.Cou

    ldnotreplicate

    Gershoffsbeneficialeffectsize

    Privilegeremoval

    Resiststemp

    tation

    .10

    Same

    Isolation

    Resiststemp

    tation

    .01

    Same

    Lovewithdrawal

    Resiststemp

    tation

    .37

    Same

    Uncontrolledcross-sectionalstudies

    Aronfreed(1961)

    12B,G(M)

    Sixth-gradesample

    120

    Primarilysensitization

    (PP&uncontrolled

    verbalassaults)vs.

    primarilyinduction

    (lovewithdrawal,

    encouraging

    responsibility,and

    explanations;based

    onresponsesto

    vignettes;

    predominantPP)

    Internaland

    external

    motivation

    sfor

    moralcorr

    ectionsin

    projective

    story

    completions

    .16

    2

    2contingencytables

    with6internal

    and6externalmoralm

    otivations,

    counting9non-signific

    antassociations

    as.00.Gershoffusedo

    nlythe

    significantassociationwithreparations

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    12 Larzelere and Kuhn

    TableI.Continued

    Basisofeffect

    size&

    Age,Gender

    Discipline

    Effect

    discrepancies

    from

    Study

    (Parent)a

    Sample

    N

    tacticb

    Outcome

    sizec(d)

    Gershoff(2002)

    Burtonetal.(1961)

    4B,G(M)

    Privatenurseryschool

    sample

    77Interviewerratingof

    PPasusual

    disciplinetechnique

    (predominantPP)

    Resiststemptation

    (labtest)

    .35

    From2

    2contingencytable.Gershoff

    didnotincludethisoutcome

    Reasoningratedas

    usualtechnique

    Resiststemptation

    .08

    2

    2contingencytable

    Scoldingratedas

    usualtechnique

    Resiststemptation

    .25

    Same

    Privilegeremoval

    ratedasusual

    technique

    Resiststemptation

    .63

    Same

    Isolationratedas

    usualtechnique

    Resiststemptation

    .12

    Same

    Interviewerratingof

    frequencyof

    spanking,slapping,

    andshaking(severe

    PP)

    Resiststemptation

    .00

    Tablenotgiven,estimate

    dat.00dueto

    non-significance

    Ratedfrequencyof

    reasoning

    Resiststemptation

    .61

    2

    2contingencytable

    Ratedfrequencyof

    scolding

    Resiststemptation

    .00

    Non-significantassociation

    Ratedfrequencyof

    privilegeremoval

    Resiststemptation

    .34

    2

    2contingencytable.

    Ratedfrequencyof

    isolation

    Resiststemptation

    .00

    Non-significantassociation

    Ratedfrequencyof

    lovewithdrawal

    Resiststemptation

    .33

    2

    2contingencytable

    Interviewerratingof

    frequencyof

    spanking,slapping,

    andshaking(severe

    PP)

    Conscience(initial

    childactionsafter

    wrongdoing)

    .62

    Gershoffusedonlythiscorrelationfrom

    thestudy

    Ratedfrequencyof

    reasoning

    Conscience

    .36

    Correlation

    Ratedfrequencyof

    scolding

    Conscience

    .00

    Non-significantr

    Ratedfrequencyof

    privilegeremoval

    Conscience

    .32

    Correlation

    Ratedfrequencyof

    isolation

    Conscience

    .30

    Correlation

    Ratedfrequencyof

    lovewithdrawal

    Conscience

    .00

    Non-significantr

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    Physical Punishment vs. Alternative Tactics 13

    Lytton(1977)

    2B(M,F)

    Volunteers

    90

    Maternalandpaternal

    frequenciesofPP

    (customaryPP)

    Compliance(two

    measures)and

    conscience

    (1)

    .04Averageofbetasof2pare

    ntsfor3

    outcomes,assuming.00

    for

    non-significantpredictors.Gershoff

    onlyusedtheonesignifi

    cant

    correlation

    Ratingofmothers

    induction(e.g.,

    explanationof

    orders)

    Compliancea

    nd

    conscience

    .06Non-significantrs,butmostlyinthe

    indicateddirection,acco

    rdingtothe

    text

    Ratingofmothers

    verbal

    psychological

    punishment

    (criticism,

    withdrawaloflove)

    Compliancea

    nd

    conscience

    .11Averageofbetasforthree

    outcomes,

    assuming.00fornon-sig

    nificant

    predictors

    Maternalfrequencyof

    lovewithdrawal

    Compliancea

    nd

    conscience

    .06Non-significantrs,butmostlyinthe

    indicateddirection,acco

    rdingtothe

    text

    Searsetal.(1957)

    5B,G(M)

    Kindergartensample

    160ExtentofPP,

    combiningseverity

    andfrequency

    (severePP)

    Conscience

    .41Correlationsofhighvs.lowuseofeach

    disciplinarytacticwithc

    onscience,

    similartoGershoff

    Reasoning

    Conscience

    .37

    Same

    Privilegeremoval

    Conscience

    .14

    Same

    Isolation

    Conscience

    .00Non-significantr

    Lovewithdrawal

    Conscience

    .18Correlationsofhighvs.lowlove

    withdrawal&conscienc

    e

    Yarrowetal.(1968)

    4B,G(M)

    Nurseryschoolsample

    86

    Reporteduseof

    physical

    punishmentfrom

    vignettesabout

    extreme

    disobedience

    (conditionalPP)

    Conscience(m

    aternal

    report)

    .02Correlation.Thisoutcome

    notin

    Gershoff

    Useofreasoningfrom

    vignettes

    Conscience

    .22

    Correlation

    Useofscoldingfrom

    vignettes

    Conscience

    .18

    Same

    Useofprivilege

    removalfrom

    vignettes

    Conscience

    .22

    Same

    Useofisolationfrom

    vignettes

    Conscience

    .30

    Same

    Useofdivertingfrom

    vignettes

    Conscience

    .32

    Same

    Useoflove

    withdrawalfrom

    vignettes

    Conscience

    .04

    Same

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    14 Larzelere and Kuhn

    TableI.Continued

    Basisofeffectsize&

    Age,Gender

    Discipline

    Effect

    discrepanciesfrom

    Study

    (Parent)a

    Sample

    N

    tacticb

    Outcom

    e

    sizec(d)

    Gershoff(2

    002)

    Prosocialbehavior

    Uncontrolledlongitudinalstudies

    Zahn-Waxler,

    Radke-Yarrow,

    andKing(1979)

    1524monthsB,

    G(M)

    Volunteers

    16

    Proportionaluseof

    PPinemotionally

    charged

    motherchild

    interactions

    (predominantPP)

    Reparationsan

    d

    altruism4.5months

    later

    .58

    Averagecorrelationsfortime-lagdata

    forreparationsandfo

    raltruism.

    Gershoffprobablyusedtheseplus

    contemporaneousrs

    Explanationswith

    affect(proportional

    use)

    Reparationsan

    d

    altruismlate

    r

    1.25

    Same

    Positivesuggestions

    (proportionaluse)

    Reparationsan

    d

    altruismlate

    r

    .56

    Same

    Explanationswith

    neutralaffect

    (proportionaluse)

    Reparationsan

    d

    altruismlate

    r

    .10

    Same

    Physicalrestraint

    (proportionaluse)

    Reparationsan

    d

    altruismlate

    ron

    .26

    Same

    Unexplainedverbal

    prohibitions

    (proportionaluse)

    Reparationsan

    d

    altruismlate

    ron

    .70

    Same

    Ignoring

    (proportionaluse)

    Reparationsan

    d

    altruismlate

    ron

    .34

    Same

    Retrospectivestudies

    Watson(1989)

    05atT1;17at

    T2;B,G(M,

    F)

    NationalMerit

    Scholarshipfinalists

    &average

    test-takers

    2500Parentalreportof

    spankingand

    possiblytimeout

    beforeage6

    (customaryPP)

    Youth-reported

    altruism

    .00

    Correlation,using.00fo

    rnon-significant

    rs.OutcomenotinGershoff

    Parentalreportof

    withdrawalof

    privilegesand

    assigningextra

    dutiesbeforeage6

    Youth-reported

    altruism

    .00

    Non-significantrs

    Uncontrolledcross-sectionalstudies

    Hall(1994)

    45B,G(M)

    Preschoolersfrom

    highincome

    families

    41

    Frequencyof

    spankingor

    slapping,from

    ConflictTactics

    Scale(CTS)items

    (customaryPP)

    Verbalpositive

    son

    interpersona

    l

    problemsolv

    ing

    task

    .18

    Correlation.Gershoffusedonlyther

    withnonverbalnegativesonasimilar

    task,buttheequivalentrwasnot

    reportedforreasoning

    Reasoning(%of

    maximumpossible

    scoreonthreeCTS

    items)

    Verbalpositive

    son

    interpersona

    l

    problemsolv

    ing

    task

    .44

    Correlati

    on

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    Physical Punishment vs. Alternative Tactics 15

    Self-esteem

    Retrospectivestudies

    Larzelere,Klein,

    Schumm,and

    Alibrando(1989)

    012atT1,M=

    21atT2;B,G

    (M,F)

    HomeEconomics

    collegestudents

    157

    Spankingfrequency

    (customaryPP)

    Self-esteem

    .10

    Correlationinfullrepo

    rtmentionedin

    articlesfootnote.Ou

    tcomenotin

    Gershoffduetonon-significantrs

    Alternative

    punishments

    (time-out,privilege

    removal,

    restitution)inall

    threeagegroups

    Self-esteem

    .08

    Correlation

    Watson(1989)

    05atT1;17at

    T2;B,G(M,

    F)

    NationalMerit

    Scholarshipfinalists

    &average

    test-takers

    2500

    Parentalreportof

    spankingand

    possiblytimeout

    beforeage6

    (customaryPP)

    Youth-repo

    rted

    neuroticism,

    self-acceptance,and

    senseofwell-being

    .03

    Correlationswiththree

    outcomes,using

    .00fornon-significan

    trs.Outcomenot

    inGershoff

    Parentalreportof

    withdrawalof

    privilegesand

    assigningextra

    dutiesbeforeage6

    Neuroticism

    ,

    self-acceptance,&

    well-bein

    g

    .00

    Non-significantrs

    Uncontrolledcross-sectionalstudies

    Coopersmith(1967)

    1012B(M)

    Fifth-gradersselected

    forconsistencyor

    inconsistencyon

    measuresof

    self-esteem

    63

    Predominantuseof

    physical

    punishmentrather

    thannexttwo

    tactics,whenrules

    areviolated

    (predominantPP)

    Self-esteem

    .42

    Proportionsofthehigh

    andlow

    self-esteemgroupsw

    ithPPas

    predominantdisciplinarymethod,

    comparedtothenexttwo,tactics

    similartoGershoff

    Predominantuseof

    lovewithdrawal

    Self-esteem

    .54

    Proportionsoftheextremeself-esteem

    groupsusinglovewithdrawal

    predominantly

    Predominantuseof

    mildermanagement

    tactics(restraint,

    denial,isolation)

    morethanabove

    twotactics

    Self-esteem

    .86

    Proportionsoftheextremeself-esteem

    groupsusingmildertactics

    predominantly

    Stressdiscussionand

    reasoningtoobtain

    complianceand

    cooperation,rather

    thanforceor

    autocraticmeans

    Self-esteem

    .87

    Proportionsoftheextremeself-esteem

    groupsthatpreferredeitherofthese

    twodisciplinaryapproaches

    Competency

    Uncontrolledlongitudinalstudies

    Crowne,Conn,

    Marlowe,and

    Edwards(1969)

    5atT1,18atT2;

    B,G(M,F)

    Kindergartenchildren

    83

    Frequencyand

    severityofspanking

    byeachparent

    (severePP)

    Ambitious,

    yet

    realistica

    spirations

    andunus

    ualgoal

    shifts13yearslater

    .00

    Meanof15associationsforthree

    measuresofphysical

    punishmentand

    fiveunambiguousou

    tcomes.

    d=

    .00if

    non-significant.NotinGershoff

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    16 Larzelere and Kuhn

    TableI.Continued

    Basisofeffectsize&

    Age,Gender

    Discipline

    Effect

    discrepanciesfrom

    Study

    (Parent)a

    Sample

    N

    tacticb

    Outcom

    e

    sizec(d)

    Gershoff(2

    002)

    Reasoning

    Ambitious,rea

    listic

    aspirations,etc.

    .09

    Meanoffiveassociation

    s(onlyone

    measureofreasoning)

    Privilegeremoval

    Ambitious,rea

    listic

    aspirations,etc.

    .00

    Meanoffiveassociation

    s

    Isolation

    Ambitious,rea

    listic

    aspirations,etc.

    .00

    Meanoffiveassociation

    s

    Lovewithdrawal

    Ambitious,rea

    listic

    aspirations,etc.

    .00

    Meanoffiveassociation

    s

    Retrospectivestudies

    Watson(1989)

    05atT1;17at

    T2;B,G(M,

    F)

    NationalMerit

    Scholarshipfinalists

    &average

    test-takers

    2500Parentalreportof

    spankingand

    possiblytimeout

    beforeage6

    (customaryPP)

    ScoreonNatio

    nal

    MeritSchola

    rship

    Testandrep

    orted

    %rankinclass

    .11

    Meanoftwocorrelation

    s.Outcomenot

    inGershoff

    Parentalreportof

    withdrawalof

    privilegesand

    assigningextra

    dutiesbeforeage6

    ScoreonNatio

    nal

    MeritTestand%

    rankinclass

    .19

    Meanoftwocorrelation

    s

    Uncontrolledcross-sectionalstudies

    Hall(1994)

    45B,G(M)

    Preschoolersfrom

    highincome

    families

    41

    Frequencyof

    spankingor

    slappingonConflict

    TacticsScale(CTS)

    item(customary

    PP)

    Numberofrelevant

    solutionsin

    interpersona

    l

    conflicttask

    .73

    Correlation.Outcomen

    otinGershoff

    Reasoning(%of

    maximumpossible

    scoreonthreeCTS

    items)

    Numberofrelevant

    solutionsin

    interpersona

    l

    conflicttask

    .73

    Correlation

    aAgeinyearsunlessotherwiseindicated;M=

    mean.T1=

    Time1,T2=

    Time2;B=

    boys,G=

    girls;(M)=

    mothers,(F)=

    fathers,(B)=

    both.

    bPhysicalpunishmentiscate

    gorizedaseitherconditional,customary,severe,orpredominantusage.

    cApositivedindicatesabeneficialassociation,i.e.,thatgreateruseofthedisciplinarytacticisassociatedwithpreferablechildoutcomes,e.g.,thetacticisassociatedwithgreater

    prosocialbehaviororlessantisocialbehavior.Anegativedindicatesadetrimentalassociationbetweenthetacticandthechildoutcome.

    dThemeanpre-postgainfor

    achild-determinedrelease(1.295)wassubtractedfromthesedsforanalysesofeffectsizesofphysicalpunishment(e.g.,TableII).

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    Physical Punishment vs. Alternative Tactics 17

    about discipline. Seven of the 26 studies in thismeta-analysis were included only in the Larzelere(2000) review. They were probably excluded fromthe Gershoff (2002) review due to having unusualchild outcome variables (three studies of substanceabuse, need for power, or realistic/ambitious aspira-tions), falling outside of her search criteria (two stud-ies), being unavailable via interlibrary loan (1), or be-ing part of a study that was already included (1).

    Moderating Variables

    The following variables were coded to deter-mine whether they accounted for differences in theeffect sizes of physical punishment and alternativedisciplinary tactics. A studys design was coded aseither (1) a randomized experiment, (2) a non-

    randomized study that controlled for initial child mis-behavior with statistical controls or within-subjectanalyses, (3) a time-ordered study (longitudinal, ret-rospective, or sequential) in which the measure ofthe disciplinary tactic clearly preceded the child out-come measure (without controlling for initial misbe-havior), or (4) a cross-sectional design, in which thereferent periods for disciplinary tactics and the childoutcome overlapped in time.

    Four types of physical punishment were distin-guished. Conditionalspanking was defined as phys-ical punishment that was used primarily to back-upmilder disciplinary tactics (e.g., reasoning or time-

    out), used for defiance, or used in a controlledmanner. These definitions of conditional spankingemerged because each type demonstrated more ben-eficial outcomes (or less detrimental outcomes) thanother types of physical punishment in at least onestudy (e.g., Larzelere, Schneider, Larson, & Pike,1996; Ritchie, 1999; Straus & Mouradian, 1998). Al-though the most optimal usage might incorporateall three definitions, no study explicitly incorporatedmore than one of these definitions in its measureof physical punishment. Customary physical punish-ment was defined as typical parental usage (e.g., us-

    age or frequency), without emphasizing its severityor predominance. It could have included severe phys-ical punishment, but only to the extent typical of ordi-nary usage by parents. Overly severe physical punish-ment was based on measures that gave extra pointsfor the severity of physical punishment. Examples in-cluded shaking (Burton, Maccoby, & Allinsmith,1961), severe spankings (Sears, Maccoby, & Levin,1957), or spanking when so angry that you lost it

    (Straus & Mouradian, 1998). Finally, predominantuse of physical punishment included studies inves-tigating predominant disciplinary tactics (e.g., theprimary disciplinary tactic used) or proportional us-age (e.g., the proportion of disciplinary incidents forwhich the parents used physical punishment ratherthan milder disciplinary tactics).

    Outcome variables were grouped into four cat-egories, consisting of compliance; antisocial behav-ior (including substance use and abuse); conscienceor resistance to temptation; and positive behaviors,competencies, or emotions. Several analyses com-bined antisocial behavior and conscience into a largercategory of misbehavior inhibition, to increase statis-tical power for testing other moderating variables.

    Same-source bias was coded when an effect sizewas based solely on information provided by thesame person, as opposed to incorporating distinct

    sources of information. Two age groups distinguishedchildren averaging older or younger than 7 years atthe time of the discipline.

    Selected Meta-Analytic Details

    Most effect sizes were calculated usingJohnsons (1989) DSTAT program, followingGershoff (2002). When a study had multiple relevantstatistics, we selected statistics that minimized themethodological problems noted by Baumrind et al.(2002), including the same-source bias and corre-

    lational statistics. When a study included severalstatistics that differed on these characteristics, effectsizes were based on the stronger evidence and alsodistinguished four types of physical punishment(conditional, customary, severe, and predominantusage). In four studies, the best estimate of the effectsize controlled statistically for one or more othervariables, such as initial child misbehavior. In thosecases, the effect size was based on a standardizedregression coefficient or similar statistic, followingGlass, McGaw, and Smith (1981). In three of thosefour studies, the effect size could not be estimated

    in standard deviations units of the outcome vari-able. Therefore, those studies were coded as using adistinct standard deviation unit typical of covariance-corrected coefficients, following Glass et al. (1981).Because the effect sizes from those three studies didnot differ significantly from the other 23 studies, thedistinction was dropped for the main analyses.

    Effect sizes (ds) were corrected for an up-ward bias in small studies, using Hedges correction

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    18 Larzelere and Kuhn

    (Lipsey & Wilson, 2001). For the analyses, each ef-fect size was weighted by a function of its sample sizeand the inverse of its extremity (Lipsey & Wilson,2001, p. 49; Shadish & Haddock, 1994, p. 268).

    The calculations of effect sizes from three sets ofstudies warrant additional clarification, which is pro-vided in the appendix (the Roberts series of studies,two Larzelere studies, and Ritchie, 1999). The guid-ing principle was to base effect sizes on equivalentanalyses of physical punishment and alternative tac-tics. In addition, Larzelere et al. (1996) and Ritchie(1999) yielded different effect sizes for conditionaland customary use of physical punishment.

    Two effect sizes were included from a studywhen they were relevant for distinct cells in a partic-ular analysis. For example, several studies had effectsizes for conditional spanking and for another cate-gory of physical punishment. Those studies then con-

    tributed two different effect sizes for those two typesof physical punishment. This increased the samplesize from 26 studies to 32 relevant effect sizes in theinitial analyses of type of physical punishment.

    Following Hedges (1994), the Q statistic wasbased on ANOVA sums of squares to test hypothe-ses about whether weighted mean effect sizes var-ied significantly by moderating factors. The Q statis-tic is distributed as 2 under the null hypothesis.Most analyses of moderating variables had missingcells because all combinations of those factors werenot represented by at least one study. Consequently,the Q statistic was based on the Type IV sums of

    squares in the weighted fixed-effects ANOVA. Sta-tistical tests of whether weighted differential meansdiffered from zero used a z statistic, based on Lipseyand Wilson (2001, p. 115).

    RESULTS

    Effect Sizes of Physical Punishment by Research

    Design and Physical Punishment Type

    The effect sizes of physical punishment on childoutcomes varied significantly by type of physical

    punishment, Q(3) = 9.80, p < .05, by research de-sign, Q(3) = 28.25, p < .001, and by their interac-tion, Q(5) = 17.82, p < .01. As shown in Table II,weighted mean effect sizes appeared detrimental forsevere physical punishment (d = .22) and predom-inant physical punishment (d = .21), but were nearzero for customary and conditional physical punish-ment (ds = .06 and .05, respectively). Mean effectsizes were apparently detrimental in studies using

    correlational designs (d = .22), approached zero intime-ordered and controlled designs (ds = .10 and.08, respectively), and were apparently beneficialin studies employing randomized designs (d = .80).The interaction effect was due to the following excep-tions to the usual pattern of effect sizes become lessdetrimental or more beneficial as design quality im-proved: Customary physical punishment produced itsmost detrimental effect size in statistically controlledstudies rather than in cross-sectional studies, whereaspredominant usage yielded its most detrimental ef-fect size in time-ordered designs rather than in cross-sectional studies.

    Differential Effect Sizes by Research Design

    and Physical Punishment Type

    The next analysis investigated differentialeffectsizes by research design and type of physical punish-ment. A differential effect size is the difference be-tween the mean effect size for physical punishmentand the mean effect size for alternative disciplinarytactics in the same study using the same method-ology. The results showed that neither design northe Design Physical Punishment Type interactionwas significant, Q(3) = 4.37 and Q(5) = 8.12, respec-tively. Differential effect sizes varied only by the typeof physical punishment, Q(3) = 18.26, p < .001.

    Table III shows that differential effect sizes fa-

    vored physical punishment over alternative tacticswhen physical punishment was defined as conditional(differential d = .29) or customary (differential d =.14). (For brevity, differential d will be shortened tod from here on, which is what it would be calledto describe differences between treatment and con-trol conditions.) In contrast, differential effect sizesfavored alternative tactics over both overly severe(d = .07) and predominant physical punishment(d = .33).

    It is instructive at this point to compare the re-sults of the first two analyses. In Table II, the effect

    sizes associated with physical punishment varied sig-nificantly by research design and by the Design Physical Punishment Type interaction. In Table III,however, differential effect sizes (d for physical pun-ishment minus d for alternative tactics) did not varysignificantly by research design or by its interactionwith physical punishment type. These results indi-cate partial success in reducing confounds associ-ated with correlational evidence by using differential

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    Physical Punishment vs. Alternative Tactics 19

    Table II. Weighted Effect Sizes for Physical Punishment by Research Design and Type of Physical Punishment

    Research designType of physical

    punishment Cross-sectional Time-ordered Controlled Randomized Weighted mean d

    Predominant .22 (4) .58 (1) .05 (1) .21 (6)

    Overly severe .32 (3) .07 (4) .22 (7)

    Customary .06 (2) .10 (4) .19 (3) .06 (9)Conditional .13 (2) .30 (2) .68 (2) .80 (4) .05 (10)

    Weighted mean d .22 (11) .10 (11) .08 (6) .80 (4) .00 (32)

    Note. n of studies in parentheses. A positive effect size (d) indicates that higher physical punishment scores are

    associated with more beneficial or less detrimental child outcomes than are low scores on physical punishment.

    All mean ds are weighted by Lipsey & Wilsons equation (2001, p. 49).

    effect sizes of alternative tactics from the samestudy.

    To obtain sufficient statistical power to investi-gate hypothesized moderators of the relative effec-tiveness of physical punishment and alternative tac-tics, the following analyses drop research design as afactor because it was not a significant predictor. Like-wise, predominant usage and severe physical punish-ment were combined into one category in subsequentanalyses.

    Differential Effect Sizes by Outcomeand Physical Punishment Type

    The next set of analyses investigated whetherthe differential effect sizes of physical punishment vs.alternatives varied by type of child outcome. The re-

    sults indicated that outcome type, physical punish-ment type, and their interaction were significantlyrelated to differential effect sizes: physical pun-ishment type, Q(2) = 41.15; outcome type, Q(2) =21.15; interaction, Q(3) = 16.95, all ps < .001. As ex-pected, conditional spanking showed a more posi-tive differential effect size (d = .29) than customaryphysical punishment (d = .14), which, in turn, pro-

    duced a more positive differential effect size thansevere/predominant physical punishment (d = .12;see Tables IVVI). Unexpectedly, effect sizes morestrongly favored physical punishment for misbehav-ior inhibition (antisocial behavior and conscience;d = .12) than for either compliance (d = .00) or posi-tive behavior and affect (d = .01). The interaction ef-fect reflected the fact that the differential effect sizesfor compliance varied by type of physical punishmentmuch more than for other outcomes. Both the largestnegative and the largest positive differential effectsizes occurred for compliance. Severe/predominantphysical punishment compared less favorably withalternatives for compliance than for any other out-come, whereas conditional spanking compared morefavorably with alternative tactics for compliance thanfor any other outcome. For most outcomes, differen-tial effect sizes were positive for conditional spank-

    ing, approached zero for customary physical punish-ment, and were negative for severe or predominantusage.

    Two of the weighted means listed above de-pended heavily upon results from the largest study,a retrospective survey of substance abuse in 5044military personnel (Tennant, Detels, & Clark, 1975).Because of its unusually large sample size, this study

    Table III. Weighted Differential Effect Sizes (Physical Punishment Minus Alternative Tactics) by Research

    Design and Type of Physical Punishment

    Research designType of physical

    punishment Cross-sectional Time-ordered Controlled Randomized Weighted mean dPredominant .37 (4) .78 (1) .22 (1) .33 (6)Overly severe .11 (3) .05 (4) .07 (7)

    Customary .10 (2) .18 (4) .06 (3) .14 (9)Conditional .22 (2) .44 (2) .59 (2) .34 (4) .29 (10)

    Weighted mean d .03 (11) .17 (11) .02 (6) .34 (4) .11 (32)

    Note. n of studies in parentheses. A positive effect size (d) indicates that physical punishment is associated withmore beneficial or less detrimental child outcomes than are alternative tactics in the same studies. All mean ds

    are weighted by Lipsey & Wilsons equation (2001, p. 49).

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    20 Larzelere and Kuhn

    Table IV. Effect Sizes ofConditionala Physical Punishment Compared to Alternative Disciplinary Tactics

    Mean effect size (d)

    Alternative Alternative Conditionala Mean difference in

    disciplinary tactic Child outcome Nstudies Nchildren disciplinary tactic physical punishment effect sizesCompliance

    Reasoning Noncompliance 313 152 .03 .55 .59b

    Verbal prohibition Immediate

    compliance

    11 24 .15 .02 .17

    Threats or verbal

    power assertion

    Stop defiance 13 90 .08 .97 .89

    Privilege removal or

    time out

    Subsequent

    compliance

    12 38 .02 .01 .01

    Privilege removal Stop defiance 13 90 .33 .97 1.30

    Time out Stop defiance 13 90 .60 .97 .37

    Barrier (room timeout)

    Compliance tocommands &

    time out

    346 52 1.04 .84 .20

    Reasoning plus

    nonphysicalpunishment

    Subsequent

    compliance

    12 38 .08 .01 .09

    Ignoring Stop defiance 13 90 .02 .97 .95

    Love withdrawal Immediatecompliance

    11 24 .40 .02 .38

    Restraint, physical

    power assertion

    Stop defiance,

    compliance tocommands &

    TO

    23,6 108 .34 .85 .51

    Child release from timeout (TO)

    Compliance tocommands

    and to timeout

    26,7 34 .02 .77 .74

    Mean for compliance 7 220 .26 .68 .43b

    Antisocial behaviorReasoning Aggression 22,8 96 .22 .35 .56

    Scolding Schoolaggression

    18 58 .24 .38 .62

    Privilege removal ortime out

    Aggression 12 38 .26 .26 .00

    Privilege removal Schoolaggression

    18 58 .38 .38 .00

    Isolation School

    aggression

    18 58 .18 .38 .56

    Reasoning plus

    nonphysicalpunishment

    Aggression 12 38 .63 .26 .37

    Reasoning ornonphysical

    punishment

    Antisocial,impulsivity

    19 744 .39 -.14 .25

    Love withdrawal School

    aggression

    18 58 .24 .38 .62

    Diverting School

    aggression

    18 58 .47 .38 .85

    Mean for antisocial behavior 3 840 .35 .07 .28

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    Physical Punishment vs. Alternative Tactics 21

    Table IV. Continued

    Mean effect size (d)

    Alternative Alternative Conditionala Mean difference indisciplinary tactic Child outcome Nstudies Nchildren disciplinary tactic physical punishment effect sizes

    Conscience

    Reasoning Conscience 18 86 .22 .02 .24

    Scolding Conscience 18 86 .18 .02 .16

    Privilege removal Conscience 18 86 .22 .02 .24

    Isolation Conscience 18 86 .30 .02 .28

    Love withdrawal Conscience 18 86 .04 .02 .02

    Diverting Conscience 18 86 .32 .02 .34

    Mean for conscience 1 86 .04 .02 .06

    Grand mean 9 1050 .23 .06 .29

    Note. In the last three columns, effect sizes that are positive indicate that more beneficial outcomes are associated with greater use of(a) alternative disciplinary tactics or (b) conditional physical punishment, or that (c) more beneficial outcomes are associ-

    ated with conditional physical punishment than with alternative disciplinary tactics. Effect sizes are based on comparable statis-tics, minimizing the methodological problems noted by Baumrind et al. (2002) whenever possible. Means are weighted by sam-

    ple size and by effect size extremity according to Lipsey and Wilsons equation (2001, p. 49), with each study contributingone mean of its relevant effect sizes. Some differential effect sizes are not an exact difference of the tabled entries due to

    rounding.Studies cited: 1Chapman and Zahn-Waxler (1982), 2Larzelere et al. (1996), 3Ritchie (1999), 4Day and Roberts (1983), 5Roberts (1988),6Roberts and Powers (1990), 7Bean and Roberts (1981), 8Yarrow et al. (1968), 9Straus and Mouradian (1998).aEither (1) nonabusive backup for milder disciplinary tactics in 2- to 6-year-olds, (2) used specifically for defiance in 3- or 4-year-olds, or

    (3) used in a controlled manner (not out of control due to anger) with 214-year-olds.bSignificant heterogeneity of the effect sizes contributing to this mean, Q statistic, p < .05.p < .05, significantly different from d = .00, z statistic (only performed in the right-hand column).p < .01.p < .001.

    was weighted eight times more than the median-sized study in this meta-analysis. Excluding thisstudy, the weighted mean differential effect sizedropped to d = .00 for customary physical pun-

    ishment and to d = .02 for misbehavior inhibition(antisocial/conscience). To avoid an overly favor-able comparison between customary physical punish-ment and nonphysical punishment based solely onthis one study, we repeated all analyses excludingthe Tennant et al. (1975) study and report the re-sults separately whenever this exclusion changed thefindings.

    Tables IVVI distinguish between antisocialbehavior and conscience, even though they weretreated as misbehavior inhibition in the above anal-yses due to the small number of studies that in-

    vestigated conscience. Table IV shows that, com-pared to alternative tactics, conditional spankingwas associated with greater reductions in noncompli-ance, d = .43, z= 3.08, p < .01, and antisocial behav-ior, d = .28, z= 4.11, p < .001. Conditional spank-ing did not differ significantly from alternative tac-tics in promoting the development of conscience, butthis was based on only one cross-sectional study.

    Table V shows that, compared to alternatives, cus-tomary physical punishment was associated withgreater reductions in antisocial behavior, but this re-sult depended upon the largest study (Tennant et

    al., 1975), d = .17 with it, z= 6.56, p < .001; d = .03without it, z= 0.81, ns. Otherwise, customary phys-ical punishment was not significantly different fromalternative tactics in its associations with other out-comes. Table VI shows that, compared to alterna-tives, severe/predominant physical punishment wasassociated with less compliance, d = .99, z= 4.43,p < .001, conscience, d = .36, z= 4.48, p < .001,positive behavior and affect, d = .36, z= 2.28,p < .05, and antisocial behavior, d = .14, z= 2.23,p < .05.

    Differential Effect Sizes by Outcome, PhysicalPunishment Type, and Other Predictors

    Additional analyses investigated whether thesame-source bias, the childs age, or the short- vs.long-term timing of the outcomes influenced differ-ential effect sizes and whether they modified the

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    22 Larzelere and Kuhn

    Table V. Effect Sizes ofCustomarya Physical Punishment Compared to Alternative Disciplinary Tactics

    Mean effect size (d)

    Alternative Alternative Customarya Mean difference in

    disciplinary tactic Child outcome Nstudies Nchildren disciplinary tactic physical punishment effect sizes

    Compliance

    Reasoning Noncompliance 313 152 .07 .04 .03

    Verbal prohibition Immediatecompliance

    12 24 .15 .09 .24

    Threats or verbalpower assertion

    Stop noncompli-ance

    13 90 .02 .07 .05

    Privilege removal or

    time out

    Subsequent

    compliance

    11 38 .02 .05 .03

    Privilege removal Stop noncompli-

    ance

    13 90 .24 .07 .17

    Time out Stop noncompli-

    ance

    13 90 .16 .07 .09

    Ignoring Stop noncompli-

    ance

    13 90 .33 .07 .26

    Love withdrawal Immediate

    compliance

    12 24 .40 .09 .31

    Physical power

    assertion

    Stop noncompli-

    ance

    13 90 .20 .07 .13

    Mean for compliance 3 152 .10 .04 .06

    Antisocial behavior

    Reasoning Aggression 11 38 .01 .08 .07

    Non-contact

    punishment

    Aggression or

    substanceabuse

    21,4 3594 .07 .23 .31c

    Privilege removal Antisocial

    behavior oralcohol usage

    25,6 3285 .13 .10 .03

    Sent to room Antisocial

    behavior

    15 785 .18 .23 .05

    Mean for antisocial behavior 4 6879 .10 .06 .17bc

    Conscience

    Reasoning Conscience &

    compliance

    17 90 .06 .04 .10

    Verbal psychological

    punishment

    Conscience,

    compliance

    17 90 .11 .04 .07

    Love withdrawal Conscience,compliance

    17 90 .06 .04 .02

    Mean for conscience 1 90 .04 .04 .00

    Mental health

    Privilege removal Neuroticism,

    esteem

    16 2500 .00 .03 .03

    Positive behavior and affectReasoning Solutions &

    verbalpositives in

    problemsolving

    18 41 .59 .28 .31

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    Physical Punishment vs. Alternative Tactics 23

    Table V. Continued

    Mean effect size (d)

    Alternative Alternative Customarya Mean difference indisciplinary tactic Child outcome Nstudies Nchildren disciplinary tactic physical punishment effect sizes

    Time out, privilegeremoval, or

    restitution

    Self-esteem 19 157 .08 .10 .02

    Privilege removal Prosocialbehavior

    16 2500 .00 .00 .00

    Privilege removal Academic

    achievement

    16 2500 .19 .11 .08

    Mean for positive behavior and affect 3 2698 .08 .05 .03

    Grand mean 9 7281 .08 .06 14bc

    Note. See Table IV.Studies cited: 1Larzelere et al. (1996), 2Chapman and Zahn-Waxler (1982), 3Ritchie (1999), 4Tennant et al. (1975), 5Larzelere and

    Smith (2000), 6Watson (1989), 7Lytton (1977), 8Hall (1994), 9Larzelere et al. (1989).aCustomary physical punishment refers to typical usage by parents, e.g., via measures of usage or frequency without emphasizing

    severity or predominant usage.bSignificant heterogeneity of the effect sizes contributing to this mean, Q statistic, p < .05.c

    After dropping the largest study (Tennant et al., 1975), the differential effect size is not significantly different fromd = .

    00 and theremaining effect sizes are homogeneous.p < .05, significantly different from d = .00, z statistic (only performed in the right-hand column).p < .01.p < .001.

    main conclusions. For each new predictor, the firstquestion was whether it was associated with differ-ential effect sizes at the zero-order level (e.g., cor-relations). If so, the second question was whetherits independent contribution was significant af-ter controlling for outcome and type of physicalpunishment.

    Same-Source Bias

    Without controlling for other factors, differen-tial effect sizes favored physical punishment over al-ternative tactics more when the same source of infor-mation was used for parent and child variables thanotherwise, d = .15 vs. d = .03, Q(1) = 12.42, p