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Latent Class Analysis (latent + class_analysis)
Selected AbstractsUnderstanding the patterns and distribution of opioid analgesic dependence symptoms using a latent empirical approachINTERNATIONAL JOURNAL OF METHODS IN PSYCHIATRIC RESEARCH, Issue 2 2008L.A. Ghandour Abstract Prevalence of extramedical opioid analgesic use in the US is rising, yet little is known about the nature and extent of problems of dependence related to the use of these drugs. This study uses Latent Class Analysis to empirically define classes of past-year extramedical opioid analgesic users based on observed clustering of DSM-IV defined clinical dependence features; multinomial logistic regression is used to describe differences across these groups. The 2002,2003 public data-files of the National Survey on Drug Use and Health were used to identify 7810 extramedical opioid analgesic users in the past-year. The best-fitting four-class model identified classes that differed quantitatively and qualitatively, with 2% of the users in Class 4 (most severe) and 84% in Class 1 (least severe). Classes 2 and 3 had parallel symptom profiles, but those in Class 3 reported additional problems. Adolescents (12,17 year olds) were at higher odds of being in Class 3 versus older age groups; females were two times as likely to be in Classes 2 and 4, and those with mental health problems were at higher odds of belonging to the more severe classes. Differences by type of past year opioid users were also detected. This study sheds light on the classification and distribution of extramedical opioid analgesic dependence symptoms in the US general population, identifying subgroups that warrant immediate attention. Copyright © 2008 John Wiley & Sons, Ltd. [source] Solidarity and Conflict Between Adult Children and Parents: A Latent Class AnalysisJOURNAL OF MARRIAGE AND FAMILY, Issue 4 2006Ruben I. Van Gaalen Using multiple dimensions of solidarity and conflict in a latent class analysis, we develop a typology of adult child,parent relationships. The data (N= 4,990) are from the first wave of the Netherlands Kinship Panel Study. In descending order of relationship quality, the 5 types are harmonious (akin to relationships with friends), ambivalent (intensive exchange of material support accompanied by strain), obligatory (just keeping in touch), affective (emotionally supportive with few other meaningful exchanges), and discordant (predominantly negative engagement). The types are differentiated by gender, age, family size, geographic distance, and parental marital history, indicating that they are not fixed but are shaped by social-structural conditions. [source] Health and Subjective Well-Being in Later Adulthood: Different Health States,Different Needs?APPLIED PSYCHOLOGY: HEALTH AND WELL-BEING, Issue 1 2009Benjamin Schüz From midlife on, health problems become more prevalent. Health is one of the key determinants of subjective well-being (SWB), but examining the relation between health and SWB in later adulthood is complicated by the clustering of multiple illnesses. This article proposes Latent Class Analysis (LCA) for a parsimonious description of adult health. This article compares SWB in health classes and examines the relative importance of socioeconomic resources, pain and coping (flexible goal adjustment) for SWB. Data stem from a nation-wide representative sample of adults aged 40,85 (German Ageing Survey, DEAS; N = 3,084). LCA was used to examine different configurations of health. Multiple regression analyses in latent classes were conducted to examine predictors of SWB. LCA generated four distinct classes of health conditions: No disease (n = 807), cardiovascular diseases (n = 405), joint problems (n = 1,612) and multiple illnesses (n = 258). As expected, only small mean differences in SWB indicators were found, whereas discontinuous predictors of SWB were detected: Coping was more strongly associated with SWB in individuals with higher illness burden. LCA can be applied to describe health in later adulthood. Differential prediction patterns suggest distinct factors for SWB depending on individual health status. [source] Evidence for a hallucinogen dependence syndrome developing soon after onset of hallucinogen use during adolescenceINTERNATIONAL JOURNAL OF METHODS IN PSYCHIATRIC RESEARCH, Issue 3 2006A.L. Stone Abstract This study uses latent class methods and multiple regression to shed light on hypothesized hallucinogen dependence syndromes experienced by young people who have recently initiated hallucinogen use. It explores possible variation in risk. The study sample, identified within public-use data files of the 1999 National Household Survey on Drug Abuse (NHSDA), consists of 1186 recent-onset hallucinogen users, defined as having initiated hallucinogen use within 24 months of assessment (median elapsed time since onset of use ,12 to 13 months). The recent-onset users in this sample were age 12 to 21 at the time of assessment and were between the ages of 10 and 21 at the time of their first hallucinogen use. The NHSDA included items to assess seven clinical features often associated with hallucinogen dependence, which were used in latent class modelling. Latent class analysis, in conjunction with prior theory, supports a three-class solution, with 2% of recent-onset users in a class that resembles a hallucinogen dependence syndrome, whereas 88% expressed few or no clinical features of dependence. The remaining 10% may reflect users who are at risk for dependence or in an early stage of dependence. Results from latent class regressions indicate that susceptibility to rapid transition from first hallucinogen use to onset of this hallucinogen dependence syndrome might be influenced by hallucinogenic compounds taken (for example, estimated relative risk, RR = 2.4, 95% CI = 1.6, 7.6 for users of MDMA versus users of LSD). Excess risk of rapid transition did not appear to depend upon age, sex, or race/ethnicity. Copyright © 2006 John Wiley & Sons, Ltd. [source] The Variety of Ecstasy/MDMA Users: Results from the National Epidemiologic Survey on Alcohol and Related ConditionsTHE AMERICAN JOURNAL ON ADDICTIONS, Issue 6 2009Li-Tzy Wu ScD 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 ofmost 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 ofprimarily prescription-type drugs (ecstasy-marijuana users, 34%). Subtypes were distinguished by family income, history ofsubstance 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. [source] Comparison of best,worst and hedonic scaling for the measurement of consumer wine preferencesAUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH, Issue 3 2009S. MUELLER Abstract Background and Aims:, Best,worst scaling (BWS) is compared to standard hedonic scaling for measuring consumer wine preferences. BWS is a relatively new method for producing ratio-level scales and has gained recent attention for application in sensory research, but has not been applied to wine. Methods and Results:, Regular wine consumers (112) evaluated eight designed wines with both scaling methods in an intra-subject design over two test periods. The methods did not result in comparable product liking results. The eight wines could almost be differentiated on an aggregated level with hedonic ratings (P = 0.076); there was no significant difference with BWS. Latent class analysis was used to identify two clusters, which differed on the preferences for the designed sensory components. The BWS design had to be split into several blocks, so no complete individual measures were available, which prevented analysing heterogeneity for this method. Conclusions:, BWS needs more wines to be assessed per person in order to discriminate between red wines and to allow modelling of consumer preference heterogeneity. Respondents would have to accomplish complete individual BWS designs, which requires repeated exposure to the same set of wines over several tasting sessions. Significance of the Study:, This study demonstrates that BWS is not as suitable for sensory consumer preference measurement of red wine as hedonic rating. While BWS has shown a higher discriminative ability for different products and in non-sensory research, the factors of alcohol, tannin and memory fatigue make it less practical for red wine sensory measurement compared to hedonic rating. [source] Longitudinal patterns of gambling activities and associated risk factors in college studentsADDICTION, Issue 7 2009Anna E. Goudriaan ABSTRACT Aims To investigate which clusters of gambling activities exist within a longitudinal study of college health, how membership in gambling clusters change over time and whether particular clusters of gambling are associated with unhealthy risk behaviour. Design Four-year longitudinal study (2002,2006). Setting Large, public university. Participants Undergraduate college students. Measurements Ten common gambling activities were measured during 4 consecutive college years (years 1,4). Clusters of gambling activities were examined using latent class analyses. Relations between gambling clusters and gender, Greek membership, alcohol use, drug use, personality indicators of behavioural undercontrol and psychological distress were examined. Findings Four latent gambling classes were identified: (1) a low-gambling class, (2) a card gambling class, (3) a casino/slots gambling class and (4) an extensive gambling class. Over the first college years a high probability of transitioning from the low-gambling class and the card gambling class into the casino/slots gambling class was present. Membership in the card, casino/slots and extensive gambling classes were associated with higher scores on alcohol/drug use, novelty seeking and self-identified gambling problems compared to the low-gambling class. The extensive gambling class scored higher than the other gambling classes on risk factors. Conclusions Extensive gamblers and card gamblers are at higher risk for problem gambling and other risky health behaviours. Prospective examinations of class membership suggested that being in the extensive and the low gambling classes was highly stable across the 4 years of college. [source] Typologies of Family Functioning and Children's Adjustment During the Early School YearsCHILD DEVELOPMENT, Issue 4 2010Melissa L. Sturge-Apple Guided by family systems theory, the present study sought to identify patterns of family functioning from observational assessments of interparental, parent,child, and triadic contexts. In addition, it charted the implications for patterns of family functioning for children's developmental trajectories of adjustment in the school context across the early school years. Two-hundred thirty-four kindergarten children (129 girls and 105 boys; mean age = 6.0 years, SD = 0.50 at Wave 1) and their parents participated in this multimethod, 3-year longitudinal investigation. As expected, latent class analyses extracted 3 primary typologies of functioning including: (a) cohesive, (b) enmeshed, and (c) disengaged families. Furthermore, family patterns were differentially associated with children's maladaptive adjustment trajectories in the school context. The findings highlight the developmental utility of incorporating pattern-based approaches to family functioning. [source] Cannabis withdrawal predicts severity of cannabis involvement at 1-year follow-up among treated adolescentsADDICTION, Issue 5 2008Tammy Chung ABSTRACT Aims Controversy exists regarding the inclusion of cannabis withdrawal as an indicator of dependence in the next revision of the Diagnostic and Statistical Manual of Mental Disorders (DSM) and International Classification of Diseases (ICD). This study contrasted the concurrent and predictive validity of three operational definitions of cannabis withdrawal in a sample of treated adolescents. Design Prospective study of treated adolescents with 1-year follow-up. Setting and participants Adolescents (n = 214) were recruited from intensive out-patient treatment programs for substance abuse, and followed at 1 year (92% retention). Youth who were included in the analyses reported regular cannabis use. Measurements The number of DSM-IV cannabis abuse and dependence symptoms at baseline and 1-year follow-up, past year frequency of cannabis use at baseline and follow-up, and periods of abstinence at 1-year follow-up. Cannabis withdrawal was defined based on (i) the presence of two or more cannabis withdrawal symptoms; (ii) a definition proposed by Budney and colleagues (2006) that requires four or more withdrawal symptoms (four-symptom definition); and (iii) the use of latent class analysis to identify subgroups with similar cannabis withdrawal symptom profiles. Findings and conclusions All three definitions of cannabis withdrawal demonstrated some concurrent validity. Only the four-symptom and latent class-derived definitions of withdrawal predicted severity of cannabis-related problems at 1-year follow-up. No cannabis withdrawal definition predicted frequency of use at follow-up. Further research is needed to determine the clinical utility and validity of the four-symptom definition, as well as alternative definitions of cannabis withdrawal, to inform revisions leading to DSM-V and ICD-11. [source] Warnings in manufacturing: Improving hazard-mitigation messaging through audience analysisHUMAN FACTORS AND ERGONOMICS IN MANUFACTURING & SERVICE INDUSTRIES, Issue 6 2010Richard C. Goldsworthy Abstract Hazard mitigation, including warning development, validation, and dissemination, is an important aspect of product safety and workplace and consumer protection. Understanding our audiences,workers and consumers,is an especially important, often overlooked, aspect of risk and harm reduction efforts. In this article, particular attention is paid to audience analysis in hazard communication and warning messaging, with a focus on the potential role of latent class analysis (LCA). We provide an example of using LCA to analyze a hazardous behavior: prescription medicine sharing and borrowing. Four distinct groups of people,ranging from abstainers to at-risk sharers,are identified and discussed. Building better warnings and risk communication techniques is essential to promoting occupational and consumer safety. Audience analysis is a vital component of these efforts. LCA appears to be a worthwhile addition to our analytical toolbox by allowing risk reduction and hazard-mitigation efforts to tailor interventions to a diverse target audience. © 2010 Wiley Periodicals, Inc. [source] Are there subgroups of bulimia nervosa based on comorbid psychiatric disorders?INTERNATIONAL JOURNAL OF EATING DISORDERS, Issue 1 2005Alexis E. Duncan MPH Abstract Objective The current study sought to determine whether there are subtypes of bulimia nervosa (BN) differentiated by comorbid psychiatric disorders. Method Data on comorbid psychiatric diagnoses in female relatives of probands and controls in the Collaborative Study of the Genetics of Alcoholism (COGA) who met criteria for BN (as outlined in the 3rd Rev. ed. of the Diagnostic and Statistical Manual of Mental Disorders) were analyzed using latent class analysis. Resulting latent classes were compared on a variety of variables related to impulsive behaviors and psychological functioning. Results The best-fitting solution, a two-class model, yielded one class (72%) characterized by substance dependence, depression, antisocial personality disorder (ASPD), and anxiety disorders, and another characterized by depression. The highly comorbid class had more suicidality, more daily smokers, sought help for emotional problems, and had lower Global Assessment of Functioning (GAF) scores compared with those in the comorbid depression only class. Discussion Latent class findings suggest the existence of two classes of BN differentiated by substance dependence, impulsive behaviors, and poorer psychological functioning. © 2004 by Wiley Periodicals, Inc. [source] Solidarity and Conflict Between Adult Children and Parents: A Latent Class AnalysisJOURNAL OF MARRIAGE AND FAMILY, Issue 4 2006Ruben I. Van Gaalen Using multiple dimensions of solidarity and conflict in a latent class analysis, we develop a typology of adult child,parent relationships. The data (N= 4,990) are from the first wave of the Netherlands Kinship Panel Study. In descending order of relationship quality, the 5 types are harmonious (akin to relationships with friends), ambivalent (intensive exchange of material support accompanied by strain), obligatory (just keeping in touch), affective (emotionally supportive with few other meaningful exchanges), and discordant (predominantly negative engagement). The types are differentiated by gender, age, family size, geographic distance, and parental marital history, indicating that they are not fixed but are shaped by social-structural conditions. [source] Prospective Follow-Up of Empirically Derived Alcohol Dependence Subtypes in Wave 2 of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC): Recovery Status, Alcohol Use Disorders and Diagnostic Criteria, Alcohol Consumption Behavior, Health Status, and Treatment SeekingALCOHOLISM, Issue 6 2010Howard B. Moss Background:, We have previously reported on an empirical classification of Alcohol Dependence (AD) individuals into subtypes using nationally representative general population data from the 2001 to 2002 Wave 1 of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) and latent class analysis. Our results suggested a typology of 5 separate clusters based upon age of onset of AD, multigenerational familial AD, rates of antisocial personality disorder (ASPD), endorsement of specific AD and Alcohol Abuse (AA) criteria, and the presence of comorbid mood, anxiety, and substance use disorders (SUD). In this report, we focus on the clinical follow-up of these cluster members in Wave 2 of the NESARC (2004 to 2005). Methods:, The mean interval between NESARC Wave 1 and NESARC Wave 2 interviews was 36.6 (SD = 2.6) months. For these analyses, we utilized a Wave 2 NESARC sample that was comprised of a total of 1,172 individuals who were initially ascertained as having past-year AD at NESARC Wave 1 and initially subtyped into one of 5 groupings using latent class analysis. We identified these subtypes as: (i) Young Adult, characterized by very early age of onset, minimal family history, and low rates of psychiatric and SUD comorbidity; (ii) Functional, characterized by older age of onset, higher psychosocial functioning, minimal family history, and low rates of psychiatric and SUD comorbidity; (iii) Intermediate Familial, characterized by older age of onset, significant familial AD, and elevated comorbid rates of mood disorders SUD; (iv) Young Antisocial, characterized by early age of onset and elevated rates of ASPD, significant familial AD, and elevated rates of comorbid mood disorders and SUD; (v) Chronic Severe, characterized by later onset, elevated rates of ASPD, significant familial AD, and elevated rates of comorbid mood disorders and SUD. In this report, we examine Wave 2 recovery status, health status, alcohol consumption behavior, and treatment episodes based upon these subtypes. Results:, Significantly fewer of the Young Adult and Functional subtypes continued to meet full DSM-IV AD criteria in Wave 2 than did the Intermediate Familial, the Young Antisocial, and the Chronic Severe subtypes. However, we did not find that treatment seeking for alcohol problems increased over Wave 1 reports. In Wave 2, Young Antisocial and Chronic Severe subtypes had highest rates of past-year treatment seeking. In terms of health status, the Intermediate Familial, the Young Antisocial, and the Chronic Severe subtypes had significantly worse mental health scores than the Young Adult and Functional subtypes. For physical health status, the Functional, Intermediate Familial, Young Antisocial, and the Chronic Severe subtypes had significantly worse scores than the Young Adult subtype. In terms of alcohol consumption behavior, the Young Adult, Functional, and Young Antisocial subtypes significantly reduced their risk drinking days between Wave 1 and Wave 2, whereas the Intermediate Familial and the Chronic Severe subtypes did not. Discussion:, The results suggest that the empirical AD typology predicts differential clinical outcomes 3 years later. Persistence of full AD, treatment seeking, and worse mental health status were associated most strongly with those subtypes manifesting the greatest degree of psychiatric comorbidity. Reductions in alcohol consumption behavior and good physical health status were seen among the 2 younger subtypes. Overall, the least prevalent subtype, the Chronic Severe, showed the greatest stability in the manifestations of AD, despite having the highest rate of treatment seeking. [source] Factors Influencing the Adoption of Mass Customization: The Impact of Base Category Consumption Frequency and Need SatisfactionTHE JOURNAL OF PRODUCT INNOVATION MANAGEMENT, Issue 2 2007Andreas M. Kaplan Mass customization has received considerable interest among researchers. However, although many authors have analyzed this concept from different angles, the question of which factors can be used to spot customers most likely to adopt a mass-customized product has not been answered to a satisfactory extent until now. This article explicitly deals with this question by focusing on factors related to the base category, which is defined as the group of all standardized products within the same product category as the mass-customized product under investigation. Specifically, this article investigates the influence of a customer's base category consumption frequency and need satisfaction on the decision to adopt a mass-customized product within this base category. A set of competing hypotheses regarding these influences is developed and subsequently evaluated by a combination of partial least squares and latent class analysis. This is done by using a sample of 2,114 customers surveyed regarding their adoption of an individualized printed newspaper. The results generated are threefold: First, it is shown that there is a significant direct influence of base category consumption frequency and need satisfaction on the behavioral intention to adopt. The more frequently a subject consumes products out of the base category or the more satisfied his or her needs are due to this consumption, the higher the behavioral intention to adopt a mass-customized product within this base category. Second, the article provides an indication that base category consumption frequency has a significant moderating effect when investigating the behavioral intention to adopt in the context of the theory of reasoned action and the technology acceptance model. The more frequently a subject consumes products out of the base category, the more important will be the impact of perceived ease of use mediated by perceived usefulness. Finally, this article shows that different latent classes with respect to unobserved heterogeneity regarding the latent variables base category need satisfaction or dissatisfaction have significantly different adoption behaviors. Individuals who show a high level of need dissatisfaction are less interested in the ease of use of a mass-customized product than its usefulness (i.e., increase in need satisfaction). On the other hand, subjects who have a high degree of base category need satisfaction base their adoption decision mainly on the ease of use of the mass-customized product. These results are of managerial relevance regarding the prediction of market reactions and the understanding of the strategic use of product-line extensions based on mass-customized products. This work provides an indication that base category consumption frequency and need satisfaction positively influence the behavioral intention to adopt a mass-customized product. Hence, mass customization can be seen as one way to deepen the relationship with existing clients. [source] Sexual Dysfunction in an Internet Sample of U.S. Men Who Have Sex with MenTHE JOURNAL OF SEXUAL MEDICINE, Issue 9 2010Sabina Hirshfield PhD ABSTRACT Introduction., Relatively little is known about sexual dysfunction (SD) in men who have sex with men (MSM). Aim., In order to better understand SD symptoms in MSM, we assessed self-reported SD symptoms, individually and by latent class analysis (LCA). Methods., In 2004,2005 an Internet sample of U.S. MSM was recruited from gay-oriented sexual networking, chat and news websites. The analytic sample comprised 7,001 men aged 18 or older who reported lifetime male sex partners and oral or anal sex with a male partner in their most recent encounter within the past year. Main Outcome Measures., Seven questions on SD symptoms that occurred during the past 12 months inquired about low sexual desire, erection problems, inability to achieve an orgasm, performance anxiety, premature ejaculation, pain during sex, and sex not being pleasurable. Results., Self-reported symptoms of SD were high. Overall, 79% of men reported one or more SD symptoms in the past year, with low sexual desire, erection problems, and performance anxiety being the most prevalent. Four distinct underlying patterns of sexual functioning were identified by LCA: no/low SD, erection problems/performance anxiety, low desire/pleasure, and high SD/sexual pain. High SD/sexual pain was distinguished from the other patterns by club drug use and use of prescription and non-prescription erectile dysfunction medication before sex in the past year. Additionally, men associated with the high SD/sexual pain group were younger, single, more likely to have poor mental and physical health, and more likely to have been diagnosed with a sexually transmitted infection in the past year compared to men in the no/low SD group. Conclusions., LCA enabled us to identify underlying patterns of sexual functioning among this sample of MSM recruited online. Future research should investigate these distinct subgroups with SD symptoms in order to develop tailored treatments and counseling for SD. Hirshfield S, Chiasson MA, Wagmiller RL, Remien RH, Humberstone M, Scheinmann R, and Grov C. Sexual dysfunction in an internet sample of U.S. men who have sex with men. J Sex Med 2010;7:3104,3114. [source] Finding patterns and groupings: I. Introduction to latent class analysisACTA NEUROPSYCHIATRICA, Issue 6 2009Dusan Hadzi-Pavlovic No abstract is available for this article. [source] Applications of Taxometric Methods to Problems of Comorbidity: Perspectives and ChallengesCLINICAL PSYCHOLOGY: SCIENCE AND PRACTICE, Issue 4 2001Irwin D. Waldman We share Meehl's view that taxometric procedures hold considerable promise for elucidating questions regarding psychiatric comorbidity. Drawing on examples from the domain of childhood disruptive disorders, we discuss why the issues raised by Meehl are scientifically and pragmatically important and outline several profitable applications of taxometric methods to questions of comorbidity (e.g., estimating the statistical relations between latent taxa). We explain why taxometric methods and other sophisticated latent variable methods are needed to answer such questions and provide examples of how certain statistical methods have been used to make erroneous inferences regarding taxonicity. Several important unresolved issues bearing on the use of taxometric procedures and their application to questions of comorbidity are delineated, including (a) the distributional assumptions of taxometric methods, (b) the construct validation of provisional taxa identified by taxometric analyses, (c) the relation of taxometric methods to other latent variable techniques (e.g., latent class analysis), (d) the potential existence of spurious taxa, (e) the question of "fuzzy taxonicity," and (f) "configural taxa." We conclude with a discussion of analytic methods for characterizing and understanding the covariation between latent dimensions as opposed to taxa. [source] | |||||||||||||