DevelopmentandPsychopathology16~2004!,1029–1046 Copyright©2004CambridgeUniversityPress PrintedintheUnitedStatesofAmerica DOI:10.10170S095457940404012X Substance abuse hinders desistance in young adults’ antisocial behavior ANDREAM.HUSSONG,a PATRICKJ.CURRAN,a TERRIEE.MOFFITT,b,c AVSHALOMCASPI,b,c andMADELINEM.CARRIGa aUniversityofNorthCarolinaatChapelHill; bInstituteofPsychiatry, UniversityofLondon;and cUniversityofWisconsin–Madison Abstract Weexaminedtwohypothesesaboutthedevelopmentalrelationbetweensubstanceabuseandindividualdifferences indesistancefromantisocialbehaviorduringyoungadulthood.The“snares”hypothesispositsthatsubstanceabuse shouldresultintime-specificelevationsinantisocialbehaviorrelativetoanindividual’sowndevelopmental trajectoryofantisocialbehavior,whereasthe“launch”hypothesispositsthatsubstanceabuseearlyinyoung adulthoodslowsanindividual’soverallpatternofcrimedesistancerelativetothepopulationnormduringthis developmentalperiod.Weconductedlatenttrajectoryanalysestotestthesehypothesesusinginterviewdataabout antisocialbehaviorsandsubstanceabuseassessedatages18,21,and26inmenfromtheDunedinMultidisciplinary HealthandDevelopmentStudy~N5461!.Wefoundsignificantindividualvariabilityininitiallevelsandratesof changeinantisocialbehaviorovertimeaswellassupportforboththesnareshypothesisandthelaunchhypothesis asexplanationsforthedevelopmentalrelationbetweensubstanceabuseandcrimedesistanceinyoungmen. Demarcating one of the most striking transi- toshowthatbothprevalenceandincidenceof tionsinnormativebehaviorovertheearlylife offending appear highest during late adoles- course, young adulthood marks a significant cence and begin to drop off only in young or shift from a pattern of increasing antisocial emergingadulthood~Blumstein,Cohen,&Far- behavior in adolescence to emerging de- rington,1988;Farrington,1986!.Althoughthe sistance.Thestudyofcrimedesistanceoffers age-related decline in antisocial behavior re- auniqueperspectiveonthedevelopmentalin- mainstheleastunderstooddevelopmentalpro- terplay between substance abuse and anti- cess in life-course research on crime and socialbehaviorduringyoungadulthood.One psychopathology ~Laub & Sampson, 2001!, of the most robust empirical observations in recentstudiessuggestthatsubstanceabuseis the study of antisocial behavior, the age– highlyrelatedtoantisocialbehaviorduringthis crime curve, plots rates of crime against age period of desistance ~Fergusson & Horwood, 2000;Huang,White,Kosterman,Catalano,& Hawkins,2001;Krueger,Hicks,Patrick,Carl- WethanktheDunedinStudymembers,DunedinUnitDi- son,Iacono,&McGue,2002!. rector Richie Poulton, Unit research staff, and Study In the present article, our aim was to test founderPhilSilva.Researchassistancewasprovidedby theroleofsubstanceabuseinthedevelopmen- HonaLee Harrington. The Dunedin Multidisciplinary tal process of desistance from antisocial be- HealthandDevelopmentResearchUnitissupportedby havior in young adulthood. To this end, we theNewZealandHealthResearchCouncil.Wealsothank AlexPiqueroforhishelpfulcomments.Thisresearchre- examinedtworelatedquestions.First,weex- ceived support from the NIDA ~Grant DA15398 and amined the extent to which individual dif- DA13148!,NIMH~GrantsMH45070andMH49414!,Wil- ferences characterize the process of crime liamT.GrantFoundation,andAirNewZealand. desistance.Theage–crimecurveisanempir- Addresscorrespondenceandreprintrequeststo:Andrea ical observation describing a group-level or Hussong, CB#3270 Davie Hall, UNC-CH, Chapel Hill, NC27599-3270. population-wide trajectory, but it ignores 1029 1030 A.M.Hussongetal. potential for individual differences in de- have employed only two time points to test sistance. Second, we examined two hypoth- whether various factors reduce antisocial be- esesdescribingtheroleofsubstanceabusein havior relative to an initial assessment point thenormativepatternofdesistancefromanti- ~Bushwayetal.,2001;Laub&Sampson,2001; social behavior during young adulthood. We Moffitt, 1993; but also see Horney, Osgood, examined both of these questions in the con- & Marshall, 1995; Laub, Nagin, & Sampson, text of a longitudinal study, where we have 1998;Nagin,Farrington,&Moffitt,1995;Na- repeatedly assessed a cohort of men over an gin & Land, 1993; Piquero, Brame, Maze- 8-year period as it made the transition from rolle,&Haapanen,2001!.However,todefine adolescencetoadulthood. desistanceasadevelopmentalprocessorslow- ing rate of antisocial behavior over time, we needanalyticmethodsthattesttrajectoriesof TheProcessofCrimeDesistance behavior assessed repeatedly within the pe- riodwhendesistanceoccurs~i.e.,youngadult- Several writers have posited that the pop- hood for men!. Newly introduced statistical ulation pattern of crime desistance in young methods~e.g.,growthcurvemodels!meetthis adulthood varies in a systematic way across criterion,butsuchmethodsrequireatleastthree individuals,suchthatdesistanceisanindivid- repeatedmeasurestodefineindividualtrajec- ualized process characterized by a decline in toriesofchange~Rogosa&Willett,1985!.In antisocial behavior over time that eventually thepresentstudy,weexaminedindividualdif- leads to termination or the end of antisocial ferencesindesistanceusingrecentlyavailable activity ~Bushway, Piquero, Brody, Cauff- datathatincludeself-reportmeasuresofanti- man,&Mazerolle,2001;Piquero,Blumstein, social behavior and three occasions of mea- Brame, Haapanen, Mulvey, & Nagin, 2001!. surement in young adulthood. As such, we Thatis,therearehypothesizedtobeinterindi- provide a timely, unique, and strong test of vidualdifferencesinintraindividualchangein whether the population age–crime trajectory antisocialbehaviorovertime~Laub&Samp- masks individual variability in desistance for son,2001;Moffitt,1993!.Althoughpriorstud- men. ies are consistent with this hypothesis, this workhaslargelyreliedonmeasurementstrat- TheRoleofSubstanceAbuse egies,researchdesignsoranalytictechniques that are suboptimal to test hypotheses about Buildingonthisinitialquestion,wetestedtwo desistance ~Bushway et al., 2001; Laub & hypotheses concerning the role of substance Sampson,2001;Moffitt,1993!. abuse in the process of crime desistance in Forexample,antisocialbehaviorhasoften young adult men. Here we distinguish be- beenassessedthroughcriminaljusticerecords tween antisocial behavior, defined as behav- that,unlikeself-reportmeasures,introducethe iors that show a “disregard for, and violation riskthatdecliningratesofantisocialbehavior of, the rights of others” according to the overtimewillreflecttheimpactofincarcera- Diagnostic and Statistical Manual of Mental tion, learning to evade detection through ex- Disorders,4thed.,Textrevision~DSM-IV-TR; perience,changefromillegaltolegalantisocial American Psychological Association, 2000, activities, or ongoing antisocial behavior that p. 701!, and substance abuse.1 Many studies does not lead to arrest. Although self-report establish significant covariance between sub- measuresmayintroducetheirownbias~Bab- inski, Hartough, & Lambert, 2001; Huizinga 1. Althoughsometheoristsmayconsidersubstanceabuse & Elliot, 1986!, this effect is thought to be tobemerelyaformofantisocialbehavior,researchin constantovertime,andthusnottodistortthe thealcoholismfieldsuggeststhatthismaynotalways longitudinalpatternofcrimedesistancethatis bethecase~asrepresentedinthevaryingsubtypesof alcoholismthatmaynotincludeantisocialbehavior; commonlyobserved. Zucker,1986!.Inthecurrentmanuscript,wefocuson Moreover,researchdesignsinpreviousstud- thesetwoconstructsasseparable,althoughwerecog- ies have historically been cross-sectional or nizethattheymayberelatedhierarchicallyaswell. Substanceabuseandantisocialbehavior 1031 stanceabuseandantisocialbehaviorinyoung sistancesuchthatshort-termalterationsinthe adulthood. Mechanisms that may account for courseofantisocialbehaviorareimpactedby thiscovariationaremany,butincludethecausal substance abuse. Both models consider indi- role of substance abuse in fueling antisocial vidualdifferencesincrimedesistance,butthey behavior, the causal role of antisocial behav- suggest alternative, although not necessarily ior in leading to substance abuse, reciprocal incompatible,mechanismsthroughwhichsub- influencesbetweensubstanceabuseandanti- stance abuse influences trajectories of anti- social behavior, and shared variance due to a social behavior over time.As such, although common risk factor ~e.g., genetic liability!. bothareconsistentwithMoffitt’soriginaldef- Moreover,theprominenceofanyonemecha- initionofsnares,herewedistinguishbetween nism may vary over subpopulations of inter- thetwo.Togetherthetestingofthesedevelop- est. However, our focus here is not on what mentalhypotheseshasthepotentialtoprovide accounts for covariation between substance crucial information about individual differ- abuseandantisocialbehaviormoregenerally, ences in the process of crime desistance that butratherontherolethatsubstanceabusemay may help to identify factors that promote play in understanding crime desistance as a desistanceorforestallit. specificphenomenonofinterest.Attimeswe considerthisrelationtobepotentiallycausal, Thelaunchmodel andatothersweconsiderhowsubstanceabuse mayserveasamarkerforaprocessimpacting Perhaps the most common method for exam- crime desistance. By focusing on the impact ining individual development over time, the ofsubstanceabuseoncrimedesistancewerec- launch method is “analogous to a catapult, in ognize that we imply a direction of influence which the initial forces of the contextual an- that may reflect only part of the complexity tecedent are the major determinants of the underlyingthemoregeneralrelationbetween shape of the curve of the outcome” ~Kinder- these two constructs. Nonetheless, it is this man & Skinner, 1992, p. 166!. In such mod- veryrelationthatismostlikelytoinformtheo- els,launchingfactorsserveasdistalpredictors riesofcrimedesistancespecifically.2 ofchangeovertimeundertheassumptionthat Inthisregard,weproposedtwohypotheses such time-lagged influences are more salient in which substance abuse acts as a snare that predictors of course than are time-varying or serves to entrench young adults in prolonged contextualfactors.Theroleofsuchdistalfac- patternsofantisocialbehaviorduringaperiod tors,althoughoftendescribedincausalterms, ofnormativedesistance.Buildingonthiscon- may also be one of early identification that ceptualization of developmental snares as in- belies the effects of selection resulting from troduced by Moffitt ~1993!, here we further priordevelopmentalprocesses.Ineithercase, distinguishbetweentwomechanismsthrough whenappliedtothestudyofcrimedesistance which such factors may act. The first, cap- andsubstanceabuseinyoungadulthood,this tured by the “launch” hypothesis, posits that modelpositsthatearlysignsofsubstanceabuse substanceabuseearlyinyoungadulthoodmay predictmaintenanceofelevatedantisocialbe- both identify young men who are on a long- havioroveryoungadulthood.Thisprediction termcourseofelevatedantisocialbehavioras is thus concerned with individual differences wellassetmenonsuchacourse.Thesecond, intheinterceptsandslopescharacterizingthe forwhichweretaintheterm“snares”hypoth- trajectories of antisocial behavior over time esis, posits that substance abuse acts through ~seeFigure1!. a series of proximal influences on crime de- Previousstudiesshowsupportforthelaunch modelasanexplanationforantisocialbehav- iorduringadolescence,whensuchtrajectories 2. Wealsorecognizethatignoringthecomplexityofsuch reflectariseinantisocialbehavior.Forexam- larger sets of relations can result in biased findings ple, Munson, McMahon, and Spieker ~2001! withoutdueattentiontothiscontextinanalyticstrat- showed that greater maternal depression pre- egies.Wefurtherconsiderthisissueinthepresenta- tionofourstatisticalmodels. dicted steeper escalations in children’s exter- 1032 A.M.Hussongetal. Figure1. Acontrastofthesnaresversuslaunchhypotheses. nalizingsymptomsovertime,especiallyamong ingyoungadulthood~Horneyetal.,1995;Laub children with avoidant insecure attachments. et al., 1998; Quinton, Pickles, Maughan, & However, to our knowledge, the role of sub- Rutter, 1993!. The second set may be called stance abuse as a launching factor in young “ensnaring”factorsinthattheyinterferewith adulthood, when the expected pattern is de- thenormativedecelerationofantisocialbehav- sistance,hasyettobeexamined. ior that is observed in the population.As de- fined in the current article, snares exert a contemporaneousorshort-termeffectonanti- Thesnareshypothesis social behavior, such that the local effects of In the work of developmental criminologists snaresalterthenormativecourseofantisocial and life-course researchers ~Laub & Samp- behavior when they or their sequelae are son, 2001; Moffitt, 1993!, two sets of factors present. Unlike protective factors, the impor- have been implicated in desistance. The first tance of snares in the maintenance of anti- set is often called “protective” factors in that social behavior has rarely been empirically they hasten the process of desistance among evaluated~althoughseePiquero,Brame,etal., menatriskforcontinuedantisocialbehavior. 2001!. Research focusing on protective effects has Ensnaringfactorsandprotectivefactorsare attributedreductionsinantisocialbehaviordur- thought to play different roles in modifying ingyoungadulthoodtotheacquisitionofadult antisocial behavior during young adulthood roles and responsibilities that are incompati- ~Rutter,1987!.Althoughtheprotectiveinflu- blewithanantisociallifestyleandtochanges ences offered by a good marriage or a good in the social bonds and social controls that job may serve to actively promote desistance accompanysuchadultroles~Laubetal.,1998; during young adulthood, snares may serve to Sampson&Laub,1993!.Supportingtherole activelyretarddesistanceduringyoungadult- ofprotectivefactorsincrimedesistance,sev- hood.Assuch,a“snare”ispositedtobemore eral recent studies suggest that reduced in- than merely the opposite of a protective fac- volvementinantisocialbehaviorcoincideswith tor. By distinguishing between these two in- entryintogoodmarriagesandgoodjobsdur- fluences, we are able to differentiate how the Substanceabuseandantisocialbehavior 1033 presence of various factors impacts young these pathways may result in greater anti- adults’livesdirectly.Thisdistinctionalsohas social behavior for those who abuse sub- importantpotentialimplicationsforinterven- stancesduringadevelopmentalperiodinwhich tions. For example, desistance research that most individuals are curbing their involve- focuses on protective factors in marriage and ment in deviant behavior.Across these path- at work necessarily suggests that interven- ways, substance abuse may serve as either a tions should focus on acquiring and promot- markervariableforaprocessinfluencingsub- ing new adult roles and responsibilities. In stance abuse or as either a direct or indirect contrast, research that focuses on snares sug- causal factor. Our goal here is not to dis- geststhat,ifsnarescanbeidentified,interven- tinguish these roles of substance abuse but tionsshouldfocusonremovingthosebarriers rather to examine whether there is support tocrimedesistancethatarelikelytoimpedea for substance abuse to function in any one of healthytransitiontoadulthood. these roles based on its prediction of crime Despite their potential importance for in- desistance. terventionstargetingantisocialbehavior,toour In contrast to the launch hypothesis, this knowledge,littleresearchhasexaminedsuch basic prediction of the snares hypothesis is protectivefactorsandnoresearchhasdirectly concernedwithtime-varyingdeviationsinanti- tested the snares hypothesis. The paucity of social behavior away from the expected pat- studies focusing on these factors is expected tern of desistance over time. Whereas snares giventherelativelyrecentintroductionofthe are expected to alter time-specific variation constructstotheliteratureandthelackofdata- in antisocial behavior within the course of sets that can meet demands noted earlier for desistance, launching factors provide a more studiesofdesistancetoincludeself-reportdata globalpredictioninwhichsubstanceabuseal- assessed repeatedly during young adulthood. ters the actual trajectory of antisocial behav- Nonetheless,substanceabusehasbeenhypoth- ior ~see Figure 1!. However, the launch and esized to be a potent snare ~Moffitt, 1993!. snares hypotheses are not necessarily incom- Several mechanisms may account for the en- patible;forexample,substanceabuseearlyin snaringroleofsubstanceabusewithintrajec- youngadulthoodmaybothdecelerateanindi- tories of antisocial behavior. First, substance vidual’s overall pattern of crime desistance abuse has been associated with difficulties in relativetoothersduringthisperiod~alaunch conventional adult roles, the same protective prediction!andincreasethelikelihoodofanti- factors that have been found to precede socialbehaviorwithincertainpointsinyoung desistanceinantisocialandcriminalbehavior adulthood relative to that individual’s ex- ~e.g., good marriages; Bachman,Wadsworth, pected level of antisocial behavior ~a snares O’Malley, Schulenberg, & Johnston, 1997; prediction!. By examining these hypotheses Leonard & Rothbard, 2000!. Second, sub- intandem,wehopetobetterelucidatethemul- stance abuse has been associated with inter- tiple roles that substance abuse may play in rupted education and incarceration ~Sher & crimedesistanceduringyoungadulthood. Gotham,1999;Vaillant,1995!,bothofwhich havebeenproposedasadditionalsnaresfore- TheCurrentStudy stalling normative desistance. Third, sub- stance abuse may reflect a physiological In sum, we examined two hypotheses about dependencethatmotivatesantisocialbehavior theeffectofsubstanceabuseondesistancein necessary to purchase, obtain, and use sub- antisocial behavior during young adulthood. stances.Fourth,thesocialnatureofsubstance First, we tested whether the pattern of de- abuse during young adulthood may serve to sistancethattypifiesthepopulationtrajectory maintain common activities and ties with a ofantisocialbehavioramongmalesoveryoung deviant peer context. Fifth, the disinhibiting adulthood masks significant individual vari- propertiesofalcoholandotherdrugsmayin- ability.Second,wetestedwhethertheroleof creasetheoddsthatpoorjudgmentandimpul- alcoholandmarijuanaabuseinyoungadults’ sivitywillleadtoantisocialactivities.Eachof antisocialbehaviorcouldbeexplainedthrough 1034 A.M.Hussongetal. eitherasnaresoralaunchhypothesis.Accord- theDunedincohorttoothersettings,seeMof- ingtothesnareshypothesis,alcoholandmar- fitt,Caspi,Rutter,andSilva~2001!. ijuanaabuseaccountforheterogeneityinyoung Forthecurrentstudy,menwithincomplete adults’antisocialbehaviorbyactingassnares, data at age 18 ~n564! or who were missing increasingtheoddsthatyoungadultswillshow data at both ages 21 and 26 ~n 5 10! were time-specificelevationsinantisocialbehavior omitted from analyses ~final n5461 of 535 above their underlying propensity for anti- malerespondentsatage18,including438with socialbehaviorovertime.Thelaunchhypoth- completed data and 23 with partially missing esis examines whether substance abuse early data!.Thettestsshowednosignificantdiffer- in young adulthood marks a distinct overall ences between retained and omitted cases, courseofantisocialbehaviorthatfollows.By whereavailable,onantisocialbehavior,alco- testingthesehypotheses,weexamineassump- holsymptoms,ormarijuanasymptomsatages tionsaboutcrimedesistanceandmaintenance 18, 21, or 26. Detailed analyses comparing and offer a more refined specification of the groups of study members who did not take associationbetweensubstanceabuseandanti- partinassessmentsversusthosewhodidona socialbehaviorovertime. variety of family and individual characteris- ticshaverevealednogroupdifferencesasre- portedinMoffittetal.~2001!. Method Participants Measures ParticipantsaremembersoftheDunedinMulti- Alcohol abuse and marijuana abuse were as- disciplinaryHealthandDevelopmentStudy,a sessed by symptoms from the Diagnostic In- longitudinalinvestigationofhealthandbehav- terviewSchedule~DIS;Robins,Helzer,Cottler, ior in a complete birth cohort ~Silva & Stan- & Goldring, 1989!. The DIS was adminis- ton, 1996!. The study members were born in tered to participants at ages 18 ~DIS-III-R!, Dunedin, New Zealand, between April 1972 21 ~DIS-III-R!, and 26 ~DIS-IV!. Antisocial andMarch1973.Ofthese,1,037children~91% behaviorswereassessedviatheself-reportof- of eligible births, 52% males! participated in fendinginterview,whichascertainsillegalbe- the first follow-up assessment at age 3, and haviorsandconductproblems~Moffitt,Silva, theyconstitutethebasesamplefortheremain- Lynam,&Henry,1994!.Antisocialbehaviors derofthestudy.Cohortfamiliesrepresentthe and substance abuse symptoms were ascer- fullrangeofsocioeconomicstatusinthegen- tainedonthesamedaybutinseparate,coun- eral population of New Zealand’s South Is- terbalancedsessionsconductedbyinterviewers land and are primarily White; fewer than 7% who were blind to the other assessment. Be- self-identified at age 18 as Maori or Pacific causewewereinterestedinexaminingchanges Islanders. Assessments have been conducted inboththemeanandvarianceofbehaviorover at ages 3 ~n 51,037!, 5 ~n 5 991!, 7 ~n 5 time,continuityinitemcontentforeachscale 954!,9~n5955!,11~n5925!,13~n5850!, was very important. For this reason, parallel 15~n5976!,18~n5993!,21~n5961!,and itemswereselectedfromeachassessmentage most recently at age 26~n5980, 499 males, tomeasureantisocialbehavior,alcoholabuse, 96% of living cohort members!. The current andmarijuanaabuse.3 studyfocusedonself-reportdatagatheredfrom men at ages 18, 21, and 26. Rates of diag- nosed conduct disorder, substance depen- 3. AlthoughtheDunedinstudyhasaricharrayofmea- dence,andself-reporteddelinquentoffending suresextendingdowntoage3,ourconstraintforpar- in New Zealand were similar to those ob- allel measurement and our focus on the desistance characterizingantisocialbehaviorinyoungadulthood tained for surveys of same-age epidemi- guidedustofocusonages18–26inthecurrentstudy. ological samples in the United States; for Thisalsoallowedforaspecificempiricaltestofour documentationsupportinggeneralizationfrom theoreticalquestionsofinterest. Substanceabuseandantisocialbehavior 1035 Table1.Correlationmatrix Variable 1 2 3 4 5 6 7 8 9 1.Antisocialbehaviorat18 — 2.Antisocialbehaviorat21 .56 — 3.Antisocialbehaviorat26 .51 .53 — 4.Marijuanasymptomsat18 .55 .37 .36 — 5.Marijuanasymptomsat21 .50 .54 .46 .55 — 6.Marijuanasymptomsat26 .42 .40 .49 .42 .57 — 7.Alcoholsymptomsat18 .53 .37 .35 .46 .42 .31 — 8.Alcoholsymptomsat21 .44 .48 .34 .34 .53 .36 .52 — 9.Alcoholsymptomsat26 .34 .32 .40 .20 .30 .48 .34 .46 — M 1.95 1.57 1.50 0.63 1.07 1.08 2.32 3.54 2.78 SD 1.59 1.71 1.46 1.61 2.02 1.98 2.85 3.68 3.23 Reliability .67 .74 .67 .86 .86 .85 .82 .86 .84 n 461 451 455 461 446 456 461 451 456 Note:Becauseofmissingdata,n5440–461acrosscorrelationsreportedabove;allcorrelationsaresignificantat p,.000. Antisocial behavior. We used eight parallel marijuana abuse and dependence across the items assessing conduct disorder ~DSM-IV- threeassessments.Thesesymptomslargelyre- TR;American PsychiatricAssociation, 2000! flect those for substance abuse and depen- to create a variety score for antisocial behav- denceasstatedintheDSM-IV-TR~e.g.,unable ior within each period. Variety scores index tostopusing,tolerance,continuedusedespite the total number of different forms of anti- healthorsocialproblems;AmericanPsychiat- socialbehaviorinwhichaparticipanthasen- ric Association, 2000!. Each symptom was gaged as opposed to, for example, the total codedaspresentorabsentwithintheprevious frequency of antisocial acts. Previous studies year.Thetotalnumberofsymptomsendorsed suggest that variety scores may better reflect foreachscaleservedasthealcoholabuseand the extent or severity of antisocial involve- marijuana abuse scores, respectively, for the ment and these scores are consistent with a current study. Table 1 contains psychometric diagnosticapproachtoassessingconductprob- propertiesforthesevariables. lems ~Gottfredson & Hirschi, 1995; Robins, 1978!.Ourvarietyscoreswerethetotalnum- Results ber of forms of antisocial behavior in which each participant had engaged over the past Analyticstrategy twelve months. Eight forms of antisocial be- haviorwereassessed,includingbreakingand To test our hypotheses, we examined a series entering, destroying property ~illegal acts of oflatenttrajectorymodels~LTMs!.LTMs,also vandalism!, fighting ~simple assault, aggra- referredtoasgrowthcurveanalysesorrandom- vated assault, or gang fighting!, setting fires effectsmodeling,extendslatentvariableanaly- ~arson!, lying ~criminal fraud!, stealing with ses within the structural equation modeling confrontation~robbery!,stealingwithoutcon- framework to provide a flexible tool for test- frontation ~criminal theft!, and carrying or ing hypotheses of change over time and pre- using a weapon. Psychometric properties of dictors of such change ~McArdle, 1988; theresultingvariablesarereportedinTable1. Meredith & Tisak, 1984, 1990!. First, we es- timatedanunconditionallineargrowthmodel Substanceabuse. NineteenitemsfromtheDIS to examine whether the characteristics of in- assessed symptoms of alcohol abuse and de- dividualtrajectoriesofantisocialbehaviorvar- pendenceand10itemsassessedsymptomsof iedacrossmen.Second,wetestedthelaunch 1036 A.M.Hussongetal. hypothesisthroughaconditionalLTMinwhich 18, 21, and 26. Two latent factors were esti- substance abuse at age 18 served as an exog- mated: one to define the intercept of the de- enous predictor of change over time in anti- velopmental trajectory of antisocial behavior social behavior. Third, we tested the snares ~withallfactorloadingsfixedto1.0!,andone hypothesis through a time-varying covariate todefinethelinearslopeofthetrajectory~with LTM that considers the repeated measures of factor loadings set to 0, 3, and 8 to define an substanceabuseastime-varyingcovariatesto annual metric of time!. This model is pre- testtheirtime-specificinfluencesonantisocial sentedinFigure2.Ameanwasestimatedfor behavioraboveandbeyondtheinfluenceofeach theinterceptandslopefactors,andtheseval- individual’sunderlyingtrajectoryofantisocial ues represented the mean model-implied behavior.Thetime-varyingcovariateLTMal- developmentaltrajectorypooledoverallindi- lows for a direct test of our hypothesis about viduals.Avariancewasalsoestimatedforthe developmental snares given the simultaneous intercept and slope factors, representing the estimationof~a!variabilityacrossmeninin- degreeofindividualvariabilityintrajectories dividualtrajectoriesofantisocialbehaviorand around the group mean values. The covari- ~b!theassociationofsubstanceabusewithtime- ance between the two factors represented specificdeviationsawayfromthispredictedtra- the covariation between initial level and rate jectoryforeachman’santisocialbehaviorwithin of change. Larger variance estimates imply time ~see, e.g., Bryk & Raudenbush, 1992, greater individual variability in the starting p. 151; Curran & Hussong, 2002; Curran, point and the rate of change over time. Fi- Muthén,&Harford,1998!. nally, residual variances were estimated for Toavoidbiasduetothelimitedattritionin each repeated measure, and these values rep- thesample,weestimatedallmodelsusingthe resented variability in the time-specific mea- direct maximum likelihood procedure avail- sures not accounted for by the underlying ableinMplus~Muthén&Muthén,1998!and randomtrajectories. thusincludedallcaseswhohadcompletedata The unconditional LTM presented in Fig- at age 18 and at least one subsequent time ure 2 was estimated and found to fit the ob- point~finaln5461!.4Theadequacyofmodel serveddatawell,x2~1!59.31,p5.002,IFI5 fitwasevaluatedusingthelikelihoodratiotest .98,CFI5.98.Themeansofthelatentfactors ~i.e.,modelchisquare!andassociatedpvalue. showedthatthemodel-impliedtrajectoryforthe Given that our large sample size may lead to groupwascharacterizedbyasignificantinter- excessive power of the chi-square test to de- ceptof1.90differenttypesofantisocialbehav- tect even small misspecifications ~MacCal- ioratthefirsttimeperiod~t526.33,p,.001!, lum, 1990!, we also used two incremental fit andasignificantlydecreasingslopeof.05units indicesthatarelessdependentonsamplesize: peryear~t525.84,p,.001;seeFigure3!. thecomparativefitindex~CFI;Bentler,1990! Thus, the model-implied mean rate of anti- andtheincrementalFI~IFI;Bollen,1989!. social behavior significantly decreased from 1.90to1.50typesofbehaviorovertheperiod ofstudy.Further,significantvarianceestimates Trajectoriesofantisocialbehavior forboththeintercept~cZ 51.77,t58.96,p, inyoungadulthood .001!andslope~cZ 50.02,t52.69,p,.01! factorsindicatedsubstantialinterindividualvari- Toexaminethefixedandrandomcomponents abilityinintraindividualdevelopmentaltrajec- ofgrowthinantisocialbehavior,weestimated tories of antisocial behavior. Finally, the an unconditional LTM for the repeated mea- negativecorrelationbetweentheinterceptand sures of antisocial behavior reported at ages slope factors ~r52.44, t523.20, p , .01! indicatedthathigherinitialvalueswereasso- 4. Comparisonsweremadeforallanalyseswhentheef- ciatedwithsteeperdecreasesovertime. fectsofmissingdatawereestimatedusingmaximum Overall,theseresultsindicatethatthemean likelihoodinMplusversuswithresultsusinglistwise developmental trajectory of antisocial behav- deletion.Parameterschangedonlyslightlyandnosub- stantivedifferenceswerefoundacrossapproaches. ior for the sample is significantly decreasing Substanceabuseandantisocialbehavior 1037 Figure2. Theunconditionalgrowthmodelforantisocialbehavior. over time, consistent with previous findings greater than 0!, 13% showed no change and on the age–crime curve. However, we also 34% showed increasing slopes. These results foundthattherearesubstantialindividualdif- furtherunderscorethenotablevariationinin- ferences in both the initial level and rate of dividualtrajectories.Althoughthegrowthtra- changeovertime.5Figure4depictssuchvari- jectories explained 70, 49, and 78% of the ation by plotting the intercept and slope val- varianceinthetime-specificindicatorsofanti- uesforeachparticipant’sestimatedtrajectory socialbehavioratages18,21,and26,respec- against one another.6 These trajectories were tively,significantresidualvariancesremained estimated by conducting separate regression at each age. Thus, the underlying trajectory models within each case with complete data. processisaccountingforonlyaportionofthe Asindicated,53%ofparticipantsshowedde- observed variability in antisocial behavior creasing trajectories over time ~i.e., slopes withineachtimeperiod. 5. Toexaminewhethermenwhowereincarcerateddur- ingthe12-monthperiodsbeforeassessmentsatages Testofthelaunchhypothesis 21 and 26 accounted for this pattern of desistance ~Piquero,Blumstein,etal.,2001!,wereestimatedthese We next estimated a conditional LTM that modelsdroppingthe14menwhohadbeenincarcer- tested the hypothesis that substance abuse at atedformorethan1monthpriortoeitherassessment age18predictsaslowedordampenedpattern point. No meaningful changes in the findings oc- ofdesistanceintheoveralldevelopmentaltra- curred.We also reestimated these models to explore whethercasesthatshowedanotabledropinantisocial jectoryofantisocialbehavioroveryoungadult- behavioratage21relativetoages18and26servedas hood.Inotherwords,thismodeltestedwhether influentialoutliers.Again,nomeaningfulchangesin themagnitudeofinterceptsandslopesunder- thefindingsoccurred. lying antisocial behavior varied as a function 6. Notethattheseindividualcasebycaseestimatesare ofage18substanceabuse.Bothmarijuanaand for descriptive visualization purposes only. See Car- rig,Wirth,andCurran~inpress!forfurtherdetails. alcohol abuse at age 18 were included as ex- 1038 A.M.Hussongetal. Figure3. Thegroup-averagedtrajectoryofantisocialbehavior. Figure4. Thepatternoftrajectoryparametersbasedonregressionanalyseswithinindividuals. ogenous predictors of the intercept and slope fittothedata,x2 ~3!511.33,p5.01,CFI5 factors defining the trajectories of antisocial .99,IFI5.99.Greateralcoholandmarijuana behavior over ages 18, 21, and 26 ~see Fig- abuse at age 18 both significantly predicted ure 5!. The resulting model provided a good higher intercepts of the trajectories of anti-
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