Browsing by Author "Yang, Chongming"

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    A dimensional approach to understanding severity estimates and risk correlates of marijuana abuse and dependence in adults.
    (International journal of methods in psychiatric research, 2012-06) Wu, Li-Tzy; Woody, George E; Yang, Chongming; Pan, Jeng-Jong; Reeve, Bryce B; Blazer, Dan G
    While item response theory (IRT) research shows a latent severity trait underlying response patterns of substance abuse and dependence symptoms, little is known about IRT-based severity estimates in relation to clinically relevant measures. In response to increased prevalences of marijuana-related treatment admissions, an elevated level of marijuana potency, and the debate on medical marijuana use, we applied dimensional approaches to understand IRT-based severity estimates for marijuana use disorders (MUDs) and their correlates while simultaneously considering gender- and race/ethnicity-related differential item functioning (DIF). Using adult data from the 2008 National Survey on Drug Use and Health (N = 37,897), Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria for MUDs among past-year marijuana users were examined by IRT, logistic regression, and multiple indicators-multiple causes (MIMIC) approaches. Among 6917 marijuana users, 15% met criteria for a MUD; another 24% exhibited subthreshold dependence. Abuse criteria were highly correlated with dependence criteria (correlation = 0.90), indicating unidimensionality; item information curves revealed redundancy in multiple criteria. MIMIC analyses showed that MUD criteria were positively associated with weekly marijuana use, early marijuana use, other substance use disorders, substance abuse treatment, and serious psychological distress. African Americans and Hispanics showed higher levels of MUDs than Whites, even after adjusting for race/ethnicity-related DIF. The redundancy in multiple criteria suggests an opportunity to improve efficiency in measuring symptom-level manifestations by removing low-informative criteria. Elevated rates of MUDs among African Americans and Hispanics require research to elucidate risk factors and improve assessments of MUDs for different racial/ethnic groups.
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    Alcohol and drug dependence symptom items as brief screeners for substance use disorders: results from the Clinical Trials Network.
    (Journal of psychiatric research, 2012-03) Wu, Li-Tzy; Blazer, Dan G; Woody, George E; Burchett, Bruce; Yang, Chongming; Pan, Jeng-Jong; Ling, Walter
    AIM:To address an urgent need for screening of substance use problems in medical settings, we examined substance-specific dependence criteria as potential brief screeners for the detection of patients with a substance use disorder (SUD). METHODS:The sample included 920 opioid-dependent adults who were recruited from outpatient treatment settings at 11 programs in 10 U.S. cities and who completed intake assessments of SUDs for a multisite study of the National Drug Abuse Treatment Clinical Trials Network (CTN003). Data were analyzed by factor analysis, item response theory (IRT), sensitivity, and specificity procedures. RESULTS:Across all substances (alcohol, amphetamines, cannabis, cocaine, sedatives), withdrawal was among the least prevalent symptoms, while taking large amounts and inability to cut down were among the most prevalent symptoms. Items closely related to the latent trait of a SUD showed good-to-high values of area under the receiver operating characteristic curve in identifying cases of a SUD; IRT-defined severe and less discriminative items exhibited low sensitivity in identifying cases of a SUD (withdrawal for all substances; time using for alcohol and sedatives; giving up activities for sedatives). CONCLUSIONS:Study results suggest that withdrawal and time using are much less reliable indicators for a SUD than taking larger amounts than intended and inability to cut down and that the latter two items should be studied further for consideration in developing a simplified tool for screening patients for SUDs in medical settings. These findings have implications for the use of common health indicators in electronic health records systems to improve patient care.
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    Alcohol and drug use disorders among adults in emergency department settings in the United States.
    (Annals of emergency medicine, 2012-08) Wu, Li-Tzy; Swartz, Marvin S; Wu, Zunyou; Mannelli, Paolo; Yang, Chongming; Blazer, Dan G
    Improving identification and treatment for substance use disorders is a national priority, but data about various drug use disorders encountered in emergency departments (EDs) are lacking. We examine past-year substance use and substance use disorders (alcohol, 9 drug classes) among adult ED users. Prevalences of substance use and substance use disorders among ED nonusers are calculated for reference purposes.Using data from the 2007 to 2009 National Surveys on Drug Use and Health, we assessed substance use disorders among noninstitutionalized adults aged 18 years or older who responded to standardized survey questions administered by audio computer-assisted self-interviewing methods.Of all adults (N=113,672), 27.8% used the ED in the past year. ED users had higher prevalences than ED nonusers of coexisting alcohol and drug use (15.2% versus 12.1%), drug use (any drug, 16.9% versus 13.0%; marijuana, 12.1% versus 9.7%; opioids, 6.6% versus 4.1%), and alcohol or drug disorders (11.0% versus 8.5%). Among substance users, the ED group on average spent more days using drugs than the non-ED group; ED users manifested higher conditional rates of substance use disorders than ED nonusers (alcohol or drugs, 15.9% versus 11.7%; marijuana, 16.6% versus 13.2%; cocaine, 33.2% versus 22.3%; opioids, 20.6% versus 10.0%; stimulants, 18.6% versus 9.2%; sedatives, 35.0% versus 4.4%; tranquilizers, 12.4% versus 5.2%). Regardless of ED use status, substance-using young adults, men, and less-educated adults showed increased odds of having a substance use disorder.Drug use is prevalent and combined with high rates of drug use disorders among drug users treated in the ED.
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    An item response theory analysis of DSM-IV criteria for hallucinogen abuse and dependence in adolescents.
    (Addictive behaviors, 2010-03) Wu, Li-Tzy; Pan, Jeng-Jong; Yang, Chongming; Reeve, Bryce B; Blazer, Dan G
    AIM:This study applied both item response theory (IRT) and multiple indicators-multiple causes (MIMIC) methods to evaluate item-level psychometric properties of diagnostic questions for hallucinogen use disorders (HUDs), differential item functioning (DIF), and predictors of latent HUD. METHODS:Data were drawn from 2004-2006 National Surveys on Drug Use and Health. Analyses were based on 1548 past-year hallucinogen users aged 12-17 years. Substance use and symptoms were assessed by audio computer-assisted self-interviewing methods. RESULTS:Abuse and dependence criteria empirically were arrayed along a single continuum of severity. All abuse criteria indicated middle-to-high severity on the IRT-defined HUD continuum, while dependence criteria captured a wider range from the lowest (tolerance and time spent) to the highest (taking larger amounts and inability to cut down) severity levels. There was indication of DIF by hallucinogen users' age, gender, race/ethnicity, and ecstasy use status. Adjusting for DIF, ecstasy users (vs. non-ecstasy hallucinogen users), females (vs. males), and whites (vs. Hispanics) exhibited increased odds of HUD. CONCLUSIONS:Symptoms of hallucinogen abuse and dependence empirically do not reflect two discrete conditions in adolescents. Trends and problems related to hallucinogen use among girls and whites should be examined further to inform the designs of effective gender-appropriate and culturally sensitive prevention programs.
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    Construct and differential item functioning in the assessment of prescription opioid use disorders among American adolescents.
    (Journal of the American Academy of Child and Adolescent Psychiatry, 2009-05) Wu, Li-Tzy; Ringwalt, Christopher L; Yang, Chongming; Reeve, Bryce B; Pan, Jeng-Jong; Blazer, Dan G
    OBJECTIVE:To examine the psychometric properties of diagnostic criteria for prescription analgesic opioid use disorders (OUDs) and to identify background predictors of a latent continuum for OUD liability. METHOD:Data were drawn from the adolescent sample of the 2006 National Survey of Drug Use and Health. Item response theory (IRT) and multiple indicators-multiple causes methods were used to examine DSM-IV criteria for OUDs in a subsample of adolescents who reported nonmedical prescription opioid use in the past year (N = 1,290). RESULTS:Among nonmedical users of prescription opioids, the criteria of OUDs were arrayed along a single continuum of severity. All abuse criteria were endorsed at a severity level higher than D1 (tolerance) and D5 (time spent) but lower than D3 (taking larger amounts) and D4 (inability to cut down). Differential item functioning in reports of dependence symptoms across adolescents' sex and race/ethnicity were identified: withdrawal, time spent, and continued use despite medical or psychological problems. Adjusting for the effects of differential item functioning and the demographic variables examined, female subjects were more likely than male subjects to exhibit a higher level of OUD liability. CONCLUSIONS:Study findings do not support the DSM-IV's current hierarchical distinction between abuse of and dependence on prescription opioids. Abuse symptoms in adolescents are not necessarily less severe than those of dependence. There is evidence of some differential item functioning in the assessment of OUDs.
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    Delineating the maladaptive pathways of child maltreatment: A mediated moderation analysis of the roles of self-perception and social support
    (2010) Appleyard, Karen; Yang, Chongming; Runyan, Desmond K
    The current study investigated concurrent and longitudinal mediated and mediated moderation pathways among maltreatment, self-perception (i.e., loneliness and self-esteem), social support, and internalizing and externalizing behavior problems. For both genders, early childhood maltreatment (i.e., ages 0-6) was related directly to internalizing and externalizing behavior problems at age 6, and later maltreatment (i.e., ages 6-8) was directly related to internalizing and externalizing behavior problems at age 8. Results of concurrent mediation and mediated moderation indicated that early maltreatment was significantly related to internalizing and externalizing behavior problems at age 6 indirectly both through age 6 loneliness and self-esteem for boys and through age 6 loneliness for girls. Significant moderation of the pathway from early maltreatment to self-esteem, and for boys, significant mediated moderation to emotional and behavioral problems were found, such that the mediated effect through self-esteem varied across levels of social support, though in an unexpected direction. No significant longitudinal mediation or mediated moderation was found, however, between the age 6 mediators and moderator and internalizing or externalizing problems at age 8. The roles of the hypothesized mediating and moderating mechanisms are discussed, with implications for designing intervention and prevention programs.
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    Differences in onset and abuse/dependence episodes between prescription opioids and heroin: results from the National Epidemiologic Survey on Alcohol and Related Conditions.
    (Subst Abuse Rehabil, 2011-05) Wu, Li-Tzy; Woody, George E; Yang, Chongming; Mannelli, Paolo; Blazer, Dan G
    OBJECTIVES: To examine patterns of onset and abuse/dependence episodes of prescription opioid (PO) and heroin use disorders in a national sample of adults, and to explore differences by gender and substance abuse treatment status. METHODS: Analyses of data from the 2001-2002 National Epidemiologic Survey on Alcohol and Related Conditions (N = 43,093). RESULTS: Of all respondents, 5% (n = 1815) reported a history of nonmedical PO use (NMPOU) and 0.3% (n = 150) a history of heroin use. Abuse was more prevalent than dependence among NMPOUs (PO abuse, 29%; dependence, 7%) and heroin users (heroin abuse, 63%; dependence, 28%). Heroin users reported a short mean interval from first use to onset of abuse (1.5 years) or dependence (2.0 years), and a lengthy mean duration for the longest episode of abuse (66 months) or dependence (59 months); the corresponding mean estimates for PO abuse and dependence among NMPOUs were 2.6 and 2.9 years, respectively, and 31 and 49 months, respectively. The mean number of years from first use to remission from the most recent episode was 6.9 years for PO abuse and 8.1 years for dependence; the mean number of years from first heroin use to remission from the most recent episode was 8.5 years for heroin abuse and 9.7 years for dependence. Most individuals with PO or heroin use disorders were remitted from the most recent episode. Treated individuals, whether their problem was heroin or POs, tended to have a longer mean duration of an episode than untreated individuals. CONCLUSION: Periodic remissions from opioid or heroin abuse or dependence episodes occur commonly but take a long time. Timely and effective use of treatment services are needed to mitigate the many adverse consequences from opioid/heroin abuse and dependence.
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    Evaluating brief screeners to discriminate between drug use disorders in a sample of treatment-seeking adults.
    (General hospital psychiatry, 2013-01) Wu, Li-Tzy; Swartz, Marvin S; Pan, Jeng-Jong; Burchett, Bruce; Mannelli, Paolo; Yang, Chongming; Blazer, Dan G
    OBJECTIVE:The objective was to identify a potential core set of brief screeners for the detection of individuals with a substance use disorder (SUD) in medical settings. METHOD:Data were from two multisite studies that evaluated stimulant use outcomes of an abstinence-based contingency management intervention as an addition to usual care (National Drug Abuse Treatment Clinical Trials Network trials 006-007). The sample comprised 847 substance-using adults who were recruited from 12 outpatient substance abuse treatment settings across the United States. Alcohol and drug use disorders were assessed by the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Checklist. Data were analyzed by factor analysis, item response theory (IRT), sensitivity and specificity procedures. RESULTS:Comparatively prevalent symptoms of dependence, especially inability to cut down for all substances, showed high sensitivity for detecting an SUD (low rate of false negative). IRT-defined severe (infrequent) and low discriminative items, especially withdrawal for alcohol, cannabis and cocaine, had low sensitivity in identifying cases of an SUD. IRT-defined less severe (frequent) and high discriminative items, including inability to cut down or taking larger amounts than intended for all substances and withdrawal for amphetamines and opioids, showed good-to-high values of area under the receiver operating characteristic curve in classifying cases and noncases of an SUD. CONCLUSION:Findings suggest the feasibility of identifying psychometrically reliable substance dependence symptoms to develop a two-item screen for alcohol and drug disorders.
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    How do prescription opioid users differ from users of heroin or other drugs in psychopathology: results from the National Epidemiologic Survey on Alcohol and Related Conditions.
    (Journal of addiction medicine, 2011-03) Wu, Li-Tzy; Woody, George E; Yang, Chongming; Blazer, Dan G
    To study substance use and psychiatric disorders among prescription opioid users, heroin users, and non-opioid drug users in a national sample of adults.Analyses of data from the 2001-2002 National Epidemiologic Survey on Alcohol and Related Conditions (N=43,093).Four groups were identified among 9140 illicit or non-prescribed drug users: heroin-other opioid users (1.0%; used heroin and other opioids), other opioid-only users (19.8%; used other opioids but never heroin), heroin-only users (0.5%; used heroin but never other opioids), and non-opioid drug users (78.7%; used drugs but never heroin or other opioids). After adjusting for variations in socioeconomic characteristics, history of substance abuse treatment, and familial substance abuse, heroin-other opioid users had greater odds of several substance use disorders (cocaine, hallucinogen, sedative, amphetamine, and tranquilizer) as compared with the other groups; heroin-only users had reduced odds of sedative and tranquilizer use disorders as compared with other opioid-only users. Non-opioid drug users had reduced odds of all substance use disorders and other mental disorders (mood, anxiety, pathological gambling, and personality) as compared with other opioid-only users. Past-year other opioid-only users also reported slightly lower scores on quality of life than past-year non-opioid drug users.All opioid use groups had higher rates of substance use disorders than non-opioid drug users, and these rates were particularly elevated among heroin-other opioid users. Findings suggest the need to distinguish between these four groups in research and treatment as they may have different natural histories and treatment needs.
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    Racial/ethnic variations in substance-related disorders among adolescents in the United States.
    (Archives of general psychiatry, 2011-11) Wu, Li-Tzy; Woody, George E; Yang, Chongming; Pan, Jeng-Jong; Blazer, Dan G
    While young racial/ethnic groups are the fastest growing population in the United States, data about substance-related disorders among adolescents of various racial/ethnic backgrounds are lacking.To examine the magnitude of past-year DSM-IV substance-related disorders (alcohol, marijuana, cocaine, inhalants, hallucinogens, heroin, analgesic opioids, stimulants, sedatives, and tranquilizers) among adolescents of white, Hispanic, African American, Native American, Asian or Pacific Islander, and multiple race/ethnicity.The 2005 to 2008 National Survey on Drug Use and Health.Academic research.Noninstitutionalized household adolescents aged 12 to 17 years.Substance-related disorders were assessed by standardized survey questions administered using the audio computer-assisted self-interviewing method.Of 72 561 adolescents aged 12 to 17 years, 37.0% used alcohol or drugs in the past year; 7.9% met criteria for a substance-related disorder, with Native Americans having the highest prevalence of use (47.5%) and disorder (15.0%). Analgesic opioids were the second most commonly used illegal drugs, following marijuana, in all racial/ethnic groups; analgesic opioid use was comparatively prevalent among adolescents of Native American (9.7%) and multiple race/ethnicity (8.8%). Among 27 705 past-year alcohol or drug users, Native Americans (31.5%), adolescents of multiple race/ethnicity (25.2%), adolescents of white race/ethnicity (22.9%), and Hispanics (21.0%) had the highest rates of substance-related disorders. Adolescents used marijuana more frequently than alcohol or other drugs, and 25.9% of marijuana users met criteria for marijuana abuse or dependence. After controlling for adolescents' age, socioeconomic variables, population density of residence, self-rated health, and survey year, adjusted analyses of adolescent substance users indicated elevated odds of substance-related disorders among Native Americans, adolescents of multiple race/ethnicity, adolescents of white race/ethnicity, and Hispanics compared with African Americans; African Americans did not differ from Asians or Pacific Islanders.Substance use is widespread among adolescents of Native American, white, Hispanic, and multiple race/ethnicity. These groups also are disproportionately affected by substance-related disorders.
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    Recent national trends in Salvia divinorum use and substance-use disorders among recent and former Salvia divinorum users compared with nonusers.
    (Subst Abuse Rehabil, 2011-04) Wu, Li-Tzy; Woody, George E; Yang, Chongming; Li, Jih-Heng; Blazer, Dan G
    CONTEXT: Media and scientific reports have indicated an increase in recreational use of Salvia divinorum. Epidemiological data are lacking on the trends, prevalence, and correlates of S. divinorum use in large representative samples, as well as the extent of substance use and mental health problems among S. divinorum users. OBJECTIVE: To examine the national trend in prevalence of S. divinorum use and to identify sociodemographic, behavioral, mental health, and substance-use profiles of recent (past-year) and former users of S. divinorum. DESIGN: Analyses of public-use data files from the 2006-2008 United States National Surveys on Drug Use and Health (N = 166,453). SETTING: Noninstitutionalized individuals aged 12 years or older were interviewed in their places of residence. MAIN MEASURES: Substance use, S. divinorum, self-reported substance use disorders, criminality, depression, and mental health treatment were assessed by standardized survey questions administered by the audio computer-assisted self-interviewing method. RESULTS: Among survey respondents, lifetime prevalence of S. divinorum use had increased from 0.7% in 2006 to 1.3% in 2008 (an 83% increase). S. divinorum use was associated with ages 18-25 years, male gender, white or multiple race, residence of large metropolitan areas, arrests for criminal activities, and depression. S. divinorum use was particularly common among recent drug users, including users of lysergic acid diethylamide (53.7%), ecstasy (30.1%), heroin (24.2%), phencyclidine (22.4%), and cocaine (17.5%). Adjusted multinomial logistic analyses indicated polydrug use as the strongest determinant for recent and former S. divinorum use. An estimated 43.0% of past-year S. divinorum users and 28.9% of former S. divinorum users had an illicit or nonmedical drug-use disorder compared with 2.5% of nonusers. Adjusted logistic regression analyses showed that recent and former S. divinorum users had greater odds of having past-year depression and a substance-use disorder (alcohol or drugs) than past-year alcohol or drug users who did not use S. divinorum. CONCLUSION: S. divinorum use is prevalent among recent or active drug users who have used other hallucinogens or stimulants. The high prevalence of substance use disorders among recent S. divinorum users emphasizes the need to study health risks of drug interactions.
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    Subtypes of nonmedical opioid users: results from the national epidemiologic survey on alcohol and related conditions.
    (Drug and alcohol dependence, 2010-11) Wu, Li-Tzy; Woody, George E; Yang, Chongming; Blazer, Dan G
    To identify subtypes of nonmedical opioid users, gender variations in psychiatric disorders, and quality of life in a representative sample of adults.Analyses of data from the 2001-2002 National Epidemiologic Survey on Alcohol and Related Conditions (N=43,093). Latent class analysis (LCA) and multinomial logistic regression procedures examined subtypes of nonmedical opioid users.Approximately 5% (n=1815) of adults used nonmedical opioids. LCA identified four subtypes: opioid-marijuana users (33%), opioid-other prescription drug users (9%), opioid-marijuana-hallucinogen users (28%), and opioid-polydrug users (30%). Subtypes were distinguished by race/ethnicity, gender, familial substance abuse, personal history of substance abuse treatment, and patterns of psychiatric disorders. Whites and men had increased odds of being in the opioid-polydrug and opioid-marijuana-hallucinogen subtypes. The opioid-other prescription drug use subtype had disproportionately affected women who were characterized by high rates of mood/anxiety disorders and low quality of life. Across all subtypes, women and men had similarly problematic substance use disorders; however, women had more major depression and disability in the mental health domain.The generally high prevalence of psychiatric disorders among nonmedical opioid users, particularly women, underscores the need for comprehensive assessment and coordinated delivery of services to match needs with treatment, as well as continued monitoring of trends in opioid use and related problems.
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    The variety of ecstasy/MDMA users: results from the National Epidemiologic Survey on alcohol and related conditions.
    (The American journal on addictions, 2009-11) Wu, Li-Tzy; Parrott, Andy C; Ringwalt, Christopher L; Yang, Chongming; Blazer, Dan G
    This study investigates the potential heterogeneity of ecstasy or MDMA (3,4-methylenedioxy-N-methylamphetamine) users. Data came from the 2001-2002 National Epidemiologic Survey on Alcohol and Related Conditions (NESARC). Latent class analysis (LCA) and multinomial logistic regression procedures were used to identify subtypes of ecstasy users. Approximately 1.6% (n = 562) of adult participants (N = 43,093) reported lifetime ecstasy use. LCA identified three subtypes of ecstasy users. Class 1 exhibited pervasive use of most drug classes (ecstasy-polydrug users, 37%). Class 2 reported a high rate of use of marijuana and cocaine and a moderate use of amphetamines (ecstasy-marijuana-stimulant users, 29%). Class 3 was characterized by a high rate of use of marijuana and a low use of primarily prescription-type drugs (ecstasy-marijuana users, 34%). Subtypes were distinguished by family income, history of substance abuse treatment, and familial substance abuse. Class 1 exhibited the highest prevalence of disorders related to the use of marijuana (77%), tobacco (66%), amphetamines (36%), opioids (35%), sedatives (31%), and tranquilizers (30%). The recent resurgence in ecstasy use among adults underscores the need to monitor trends in its use.
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    Use of item response theory and latent class analysis to link poly-substance use disorders with addiction severity, HIV risk, and quality of life among opioid-dependent patients in the Clinical Trials Network.
    (Drug and alcohol dependence, 2011-11) Wu, Li-Tzy; Ling, Walter; Burchett, Bruce; Blazer, Dan G; Yang, Chongming; Pan, Jeng-Jong; Reeve, Bryce B; Woody, George E
    BACKGROUND:This study applied item response theory (IRT) and latent class analysis (LCA) procedures to examine the dimensionality and heterogeneity of comorbid substance use disorders (SUDs) and explored their utility for standard clinical assessments, including the Addiction Severity Index (ASI), HIV Risk Behavior Scale (HRBS), and SF-36 quality-of-life measures. METHODS:The sample included 343 opioid-dependent patients enrolled in two national multisite studies of the U.S. National Drug Abuse Treatment Clinical Trials Network (CTN001-002). Patients were recruited from inpatient and outpatient addiction treatment settings at 12 programs. Data were analyzed by factor analysis, IRT, LCA, and latent regression procedures. RESULTS:A two-class LCA model fit dichotomous SUD data empirically better than one-parameter and two-parameter IRT models. LCA distinguished 10% of severe comorbid opioid-dependent individuals who had high rates of all SUDs examined-especially amphetamine and sedative abuse/dependence-from the remaining 90% who had SUDs other than amphetamine and sedative abuse/dependence (entropy=0.99). Item-level results from both one-parameter and two-parameter IRT models also found that amphetamine and sedative abuse/dependence tapped the more severe end of the latent poly-SUD trait. Regardless of whether SUDs were defined as a continuous trait or categorically, individuals characterized by a high level of poly-SUD demonstrated more psychiatric problems and HIV risk behaviors. CONCLUSIONS:A combined application of categorical and dimensional latent approaches may improve the understanding of comorbid SUDs and their associations with other clinical indicators. Abuse of sedatives and methamphetamine may serve as a useful marker for identifying subsets of opioid-dependent individuals with needs for more intensive interventions.