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Latent profile analysis of pregnant exercise adherence and the relationship with demographic and socio-psychological factors: a multicentre cross-sectional study.

BACKGROUND: Pregnancy physical activity (PA) and exercise benefits both mothers and babies, but requires sustained adherence. Many pregnant women fail to meet recommended levels. The reasons for low adherence comprised fluctuating physiological and environmental factors. This study aims to identify discrete profiles of pregnant women based on exercise adherence and to examine differences in demographic and socio-psychological factors across these profiles. METHODS: A survey was conducted among 1,255 pregnant women in three hospitals in Shenzhen, Dongguan, and Shunde, China, using the Exercise Adherence Rating Scale (EARS), the Pregnancy Exercise Self-Efficacy Scale (P-ESES), and the Pregnancy Physical Activity Social Support Scale (P-PASSS). In the analysis, EARS items were scored higher, indicating a healthier state (e.g., sufficient time and energy). Latent profile analysis (LPA) was employed to classify adherence profiles, and multinomial logistic regression was used to examine differences in demographic, self-efficacy, and social support across four groups. RESULTS: Four profiles of exercise adherence were identified: (1) Profile 1 (16.97%), characterized by deficits in time and energy, (2) Profile 2 (15.22%), a group with sufficient time resources but the lowest self-efficacy, (3) Profile 3 (43.98%), characterized by high adherence despite moderate barriers, and (4) Profile 4 (23.83%), a group with optimal exercise adherence, confidence, and resources. Women with higher P-ESES (OR: 1.14-1.38) and P-PASSS (OR: 1.04-1.06) scores were more likely to be in Profiles 3 and 4. Additionally, women's partners who never or occasionally exercise were significantly more likely to be categorized into Profile 1 (OR = 0.18 for Profile 4 vs. Profile 1). Furthermore, the first trimester emerged as a significant risk period for lower exercise adherence, whereas overweight/obesity was independently associated with higher odds of membership in Profile 4. CONCLUSION: The study identified four distinct profiles of exercise adherence among pregnant women. 32.19% of participants were in the two lower exercise-adherence groups. Pregnant women in Profile 1 were characterized by challenges related to a lack of time and knowledge. Participants in Profile 2 showed the lowest exercise self-efficacy and social support among the four profiles. Furthermore, women in early pregnancy were more likely to have lower adherence profiles. Hence, targeted interventions addressing these specific groups are warranted to improve exercise adherence during pregnancy.

Humans↗

Understanding psychosocial adjustment in military-to-civilian transition: A latent profile analysis of ex-serving Australian Defence Force members.

Military-to-civilian transition is a critical life stage that can expose veterans to elevated risks of psychological distress, social difficulties, and reduced wellbeing. Although psychosocial factors are central to successful reintegration, little is known about distinct patterns of needs among ex-serving Australian Defence Force (ADF) members. This study used latent profile analysis (LPA) to identify psychosocial needs profiles across five domains of the Military-Civilian Adjustment and Reintegration Measure (M-CARM) in a sample of 725 ex-serving ADF members. The optimal three-class solution identified: a Low Adjustment Need (LAN) group (20.7%) reporting minimal reintegration challenges; a Cultural Adjustment Need (CAN) group (42.9%) characterized by cultural adaptation difficulties, particularly beliefs about civilians and regimentation; and a Cultural and Psychological Need (CPN) group (36.4%) showing broader challenges across beliefs about civilians, purpose and connection, regimentation, and resentment and regret. The CAN group was more likely to be male, have lower educational attainment, and have no combat deployment history. The CPN group was similarly male dominated with lower education, and was additionally characterized by Navy service, unemployment or not being in the labor force, and medical discharge. Compared with the LAN group, both CAN and CPN groups reported higher levels of depression, anxiety, posttraumatic stress, and nightmare distress, as well as poorer quality of life and greater functional impairment. These findings highlight persistent reintegration challenges among veterans and support the need for stratified support models, ranging from psychoeducation to intensive multidisciplinary care, to better address diverse psychosocial needs of ex-serving ADF members.

Australian defense force↗

Use of latent profile analysis to identify eating disorder phenotypes in an adult Australian twin cohort.

CONTEXT: The relationships among the different eating disorders that exist in the community are poorly understood, especially for residual disorders in which bingeing or purging occurs in the absence of other behaviors. OBJECTIVE: To examine a community sample for the number of mutually exclusive weight and eating profiles. DESIGN: Data regarding lifetime eating disorder symptoms and weight range were submitted to a latent profile analysis. Profiles were compared regarding personality, current eating and weight, retrospectively reported life events, and lifetime depressive psychopathology. SETTING: Longitudinal study among female twins from the Australian Twin Registry in whom eating was assessed by a telephone interview. PARTICIPANTS: A community sample of 1002 twins (individuals) who had participated in earlier waves of data collection. MAIN OUTCOME MEASURES: Number and clinical character of latent profiles. RESULTS: The best fit was a 5-profile solution with women who were (1) of normal weight with few lifetime eating disorders (4.3%), (2) overweight (10.6% had a lifetime eating disorder), (3) underweight and generally had no eating disorders except for 5.3% who had restricting anorexia nervosa, (4) of low to normal weight (89.0% had a lifetime eating disorder), and (5) obese (37.0% had a lifetime eating disorder). Each profile contained more than 1 type of lifetime eating disorder except for the third profile. Women in the first and third profiles had the best functioning, with women in the fourth and fifth profiles having similarly poorer functioning. The women in the fourth group had a symptom profile distinctive from the other 4 groups in terms of severity; they were also more likely to have had lifetime major depression and suicidality. CONCLUSION: Lifetime weight ranges and the severity of eating disorder symptoms affected clustering more than the type of eating disorder symptom.

Adult↗

Online Social Anxiety in the Digital Age: Transitions, Predictors, and Mental Health Associations in Emerging Adulthood.

BACKGROUND: Online social anxiety (OSA), a multidimensional form of social evaluative anxiety in online social contexts, disproportionately affects emerging adults who constitute the largest active group of media users and face heightened psychological sensitivity due to growing pressures and immature sociocognitive regulation during the transition to adulthood. However, its heterogeneity, transitions, and longitudinal associations with mental health outcomes remain underexplored. METHODS: This study utilized data from two waves of a three-wave longitudinal survey, with 849 Chinese participants (Meanage = 21.6 years; 50.4 percent female) assessed at 4-month intervals. Individuals were classified using latent profile analysis and the stability and changes of profiles were assessed via latent transition analysis (LTA). Multinomial logistic regressions were conducted separately at baseline and follow-up to identify correlates of profile membership. Predictors of profile transitions were examined using manual three-step LTA models, and associations between latent transition patterns and follow-up mental health outcomes were examined using BCH-LTA distal outcome analyses controlling for the corresponding baseline symptom level. RESULTS: Four profiles of OSA were identified: low, privacy-sensitive, moderate-high, and high OSA. Extreme profiles (low/high OSA) showed high stability (80.4 percent and 79.1 percent), while privacy-sensitive OSA exhibited the lowest stability (55.1 percent). Profile memberships were influenced by social-cognitive biases and digital interaction, particularly fear of negative evaluation and online interpersonal trust, whereas profile transitions were mainly associated with anxiety. Transitions toward less severe OSA profiles were generally associated with better subsequent mental health, whereas transitions toward more severe profiles corresponded to poorer outcomes, particularly for offline social anxiety. CONCLUSION: OSA was heterogeneous in its manifestation, severity and transitions. Personalized and early interventions targeting profile-specific vulnerabilities are critical to prevent the worsening of OSA and mitigate its psychological burden.

Humans↗

What is chronic fatigue syndrome? Heterogeneity within an international multicentre study.

OBJECTIVE: We sought to compare the characteristics of patients presenting with chronic fatigue (CF) and related syndromes in eight international centres and to subclassify these subjects based on symptom profiles. The validity of the subclasses was then tested against clinical data. METHOD: Subjects with a clinical diagnosis of CF completed a 119-item self-report questionnaire to provide clinical symptom data and other information such as illness course and functional impairment. Subclasses were generated using a principal components-like analysis followed by latent profile analysis (LPA). RESULTS: 744 subjects returned complete data sets (mean age 40.8 years, mean length of illness 7.9 years, female to male ratio 3:1). Overall, the subjects had a high rate of reporting typical CF symptoms (fatigue, neuropsychological dysfunction, sleep disturbance). Using LPA, two subclasses were generated. Class one (68% sample) was characterized by: younger age, lower female to male ratio; shorter episode duration; less premorbid, current and familial psychiatric morbidity; and, less functional disability. Class two subjects (32%) had features more consistent with a somatoform illness. There was substantial variation in subclass prevalences between the study centres (Class two range 6-48%). CONCLUSIONS: Criteria-based approaches to the diagnosis of CF and related syndromes do not select a homogeneous patient group. While substratification of patients is essential for further aetiological and treatment research, the basis for allocating such subcategories remains controversial.

Adult↗

Storm and Stress 2.0? A Dual-Factor, Person-Centered Analysis of Adolescent Well-being Across Two Year 7 Cohorts and Gender.

PURPOSE: Concerns about the mental health and well-being of younger generations is a recurring theme across countries and time. Adolescence is debated as a period of volatility ("storm and stress") or growth. Recent trends have reignited worries about youth mental health and well-being, particularly for females, and revived a deficit-based view of adolescence. To advance understanding, this study adopts a dual-factor approach that incorporates both negative and positive well-being domains. Mental health trends were compared across two grade-matched Australian adolescent cohorts assessed 5 years apart. METHODS: Data were drawn from cross-sectional cohorts of year 7 students (12-13 years) in one Australian jurisdiction: 2,085 in 2018 and 2,378 in 2023. Positive affect, happiness, resilience, depression, and anxiety were assessed using latent profile analysis to identify mental health profiles, which were then compared between cohorts and gender. RESULTS: Four profiles were identified: complete mental health, symptomatic but positive, resilient but disaffected, and troubled. Approximately 80% of students were classified in profiles reflecting some positive mental health. Between 2018 and 2023, the proportion with complete mental health declined by 7.93%, while those categorized as troubled increased by 4.76%. Declines were most pronounced among female students. DISCUSSION: Findings highlight both resilience and vulnerability in adolescent mental health. While most students continue to show positive well-being, the decline among females signals an urgent need for gender-sensitive approaches. At the same time, the results add nuance to accounts of a youth mental health 'crisis' to some degree, by highlighting positive domains of well-being which are often overlooked.

Humans↗

Persistent trauma three decades after the Halabja massacre: psychological symptom profiles and hair cortisol levels in gas attack survivors.

BACKGROUND: Survivors of the 1988 Halabja chemical attack have experienced severe, chronic trauma, yet limited research has examined the long-term psychological and biological consequences of chemical warfare exposure more than three decades later. AIMS: To examine long-term post-traumatic stress disorder (PTSD) symptoms, depression/anxiety symptoms, somatic symptoms and perceived stress among survivors of the Halabja chemical attack, and to investigate the associations of trauma exposure, sociodemographic factors and hair cortisol concentrations (HCCs) with psychological symptom severity and symptom profiles. METHOD: A total of 209 survivors of the Halabja chemical attack participated in structured interviews using culturally adapted and field-tested instruments, including the Post-Traumatic Stress Disorder Checklist for DSM-5, Hopkins Symptom Checklist-25, the Patient Health Questionnaire-13, the Perceived Stress Scale-14 and an adapted War and Adversity Exposure Checklist-26. Hair cortisol and cortisone concentrations were assessed as biomarkers of chronic stress. Data were analysed using correlations, independent-samples t-tests, multiple linear regression analyses, multinomial logistic regression and latent profile analysis (LPA). RESULTS: Survivors demonstrated a substantial long-term psychological symptom burden. Overall, 87.6% of participants exceeded the cut-off for probable PTSD symptoms, and 75.1% exceeded the cut-off for elevated depression/anxiety symptoms. Most participants (81.8%) reported exposure to 11 or more lifetime traumatic events. Men reported significantly greater cumulative trauma exposure, whereas women reported significantly greater somatic symptom severity. Higher educational attainment and employment were consistently associated with lower psychological symptom severity across multiple outcomes. HCCs were not significantly associated with PTSD symptoms or latent symptom-profile membership after adjustment for trauma exposure and psychosocial variables. The LPA identified four symptom-severity classes characterised by differing levels of PTSD and depression/anxiety symptoms. Greater cumulative trauma exposure and lower social support were associated with membership in more severe symptom classes. CONCLUSIONS: Survivors of the Halabja chemical attack continue to experience substantial psychological distress more than three decades after exposure. Long-term symptom severity appears to be more strongly associated with cumulative trauma exposure and psychosocial adversity than with HCCs. The findings highlight substantial heterogeneity in symptom presentation and support the need for long-term, culturally sensitive and trauma-informed mental health interventions for survivors of chemical warfare and mass violence.

Halabja chemical attack↗

Patterns of responses on health-related quality of life questionnaires among patients with HIV/AIDS.

BACKGROUND: Health-related quality of life (HRQoL) has become an important facet of HIV/AIDS research. Typically, the unit of analysis is either the total instrument score or subscale score. Developing a typology of responses across various HRQoL measures, however, may advance understating of patients' perspectives. METHODS: In a multicenter study, we categorized 443 patients' responses on utility measures (time-tradeoff, standard gamble, and rating scale) and the HIV/AIDS-Targeted Quality of Life (HAT-QoL) scale by using latent profile analysis to empirically derive classes of respondents. We then used linear regressions to identify whether class membership is associated with clinical measures (viral load, CD4, time since diagnosis, highly active antiretroviral therapy [HAART]) and psychosocial function (depressed mood, alcohol use, religious coping). RESULTS: Six classes were identified. Responses across the HAT-QoL subscales tended to fall into 3 groupings--high functioning (Class 1), moderate functioning (Classes 2 and 3), and low functioning (Classes 4 to 6); utility measures further distinguished individuals among classes. Regression analyses comparing those in Class 1 with those in the other 5 found significantly more symptoms of depression, negative religious coping strategies, and lower CD4 counts among subjects in Class 1. Those in Class 5 had been diagnosed with HIV longer, and members of Class 6 reported significantly less alcohol consumption, had higher viral loads, and were more likely to receive HAART. CONCLUSION: Patients with HIV respond differentially to various types of HRQoL measures. Health status and utility measures are thus complementary approaches to measuring HRQoL in patients with HIV.

Adaptation, Psychological↗

Subgroups of Alzheimer's disease based on cerebrospinal fluid molecular markers.

Alzheimer's disease, the most common cause of dementia, is multifactorial and heterogeneous; its diagnosis remains probable. We postulated that more than one disease mechanism yielded Alzheimer's histopathology, and that subgroups of the disease might be identified by the cerebrospinal fluid (CSF) levels of proteins associated with senile (neuritic) plaques and neurofibrillary tangles. We immunoassayed levels of tau, ubiquitin, and Abeta(1-42) in retrospectively collected CSF samples of 468 clinically diagnosed Alzheimer's disease patients (N = 353) or non-Alzheimer's subjects (N = 115). Latent profile analysis assigned each subject to a cluster based on the levels of these molecular markers. Alzheimer's disease was subdivided into at least five subgroups based on CSF levels of Abeta(1-42), tau, and ubiquitin; each subgroup presented a different clinical profile. These subgroups, which can be identified by CSF analysis, might benefit differently from different therapeutic drugs.

Aged↗

Personality traits after recovery from eating disorders: do subtypes differ?

OBJECTIVE: We compared individuals recovered from anorexia (AN) and bulimia nervosa (BN) to determine characteristics that are shared by or distinguish eating disorder (ED) subtypes. METHOD: Sixty women recovered for > or = 1 year from AN or BN were compared with 47 control women (CW). Assessments included the Yale-Brown-Cornell Eating Disorder Scale, the Spielberger State-Trait Anxiety Inventory, the Beck Depression Inventory, the Yale-Brown Obsessive Compulsive Scale, the Temperament and Character Inventory, and Structured Clinical Interviews for DSM-IV. RESULTS: Individuals recovered from an ED had similar scores for mood and personality variables that were significantly higher than the scores for CW. Few recovered subjects had Cluster B personality disorder. Most individuals recovered within 6 years of their ED onset. A latent profile analysis identified an "inhibited" and "disinhibited" cluster based on personality traits. CONCLUSION: A wide range of symptoms persist after recovery and do not differ between subtypes of ED. These findings may aid in identifying traits that create vulnerabilities for developing an ED.

Adult↗

Personality subtyping and bulimia nervosa: psychopathological and genetic correlates.

BACKGROUND: There is empirical evidence suggesting that individuals with bulimia nervosa vary considerably in terms of psychiatric co-morbidity and personality functioning. In this study, latent profile analysis was used to attempt to identify clusters of bulimic subjects based on psychiatric co-morbidity and personality. METHOD: A total of 178 women with bulimia nervosa or a subclinical variant of bulimia nervosa completed a series of self-report inventories of co-morbid psychopathology and personality, and also provided a buccal smear sample for genetic analyses. RESULTS: Three clusters of bulimic women were identified: an affective-perfectionistic cluster, an impulsive cluster, and a low co-morbid psychopathology cluster. The clusters showed expected differences on external validation tests with both personality and eating-disorder measures. The impulsive cluster showed the highest elevations on dissocial behavior and the lowest scores on compulsivity, while the affective-perfectionistic cluster showed the highest levels of eating-disorder symptoms. The clusters did not differ on genetic variations of the serotonin transporter gene. CONCLUSIONS: This study corroborates previous findings suggesting that the bulimia nervosa diagnostic category is comprised of three classes of individuals based on co-morbid psychopathology and personality. These differences may have significant etiological and treatment implications.

Adolescent↗

Profiles of externalizing behavior problems for boys and girls across preschool: the roles of emotion regulation and inattention.

Although externalizing behavior typically peaks in toddlerhood and decreases by school entry, some children do not show this normative decline. A sample of 383 boys and girls was assessed at ages 2, 4, and 5 for externalizing behavior and at age 2 on measures of emotion regulation and inattention. A longitudinal latent profile analysis was performed and resulted in 4 longitudinal profiles of externalizing behavior for each gender. Poor emotion regulation and inattention were important predictors of membership in the chronic-clinical profile for girls, whereas socioeconomic status and inattention were important predictors of membership in the chronic-clinical profile for boys. Results are discussed with respect to the development of adaptive skills that lead to normative declines in externalizing behavior across childhood.

Acting Out↗

Predicting alcohol patterns in first-year college students through motivational systems and reasons for drinking.

In the present study, a typological approach was used to identify patterns of alcohol use in a sample of 533 college freshmen students (<21 years old; 342 women; 191 men), on the basis of quantity and frequency of consumption, and alcohol-related problems. Personality (sensitivity to reward, SR; sensitivity to punishment, SP) and reasons for drinking were examined as correlates of drinking patterns through a mediational model. Analyses were done separately by gender. Latent profile analyses suggested 5 drinking patterns for both genders, including 3 problematic groups. SR was only associated with the problematic drinking patterns, and enhancement, coping, and social reasons for drinking mediated this relationship. These findings demonstrate the utility of latent profile analysis for identifying a drinking typology and for integrating personality and drinking motives to distinguish drinking patterns.

Adolescent↗

[Characteristic analysis on the anions and pH profiles of rainwater of Zhoushan Archipelago].

Rainwater samples were collected at Zhoushan Archipelago in 2002 - 2003, 4 main anion concentrations (F-, Cl-, NO3-, SO4(2-)) and pH value of rainwater sample were determined. The concentration variation range and character were depicted. Principal component analysis (PCA) and factor analysis (FA) were used to acquire a further knowledge on the characteristics of anions and pH value. Distribution character of samples was clearly depicted in the new PC1-PC2 ordinate generated by orthogonal projection and the reasons that caused the outliers in samples were discussed. In order to get the latent variables which most distinguishably effect the sample distribution, data profiles were investigated by factor analysis: two latent variables were responsible for the sample distribution within sufficient analysis accuracy, SO4(2-) -NO3- factor (FA1), called as "anthropogenic factor", and Cl- (FA2), called as "marine factor", which corresponding to PC1 and PC2 in orthogonal projection respectively. Results from factor analysis were more practical than from orthogonal projection, that is, the reasons attributed the outlier sample distribution at Zhoushan Archipelago were ascribed into two latent variables: anthropogenic factor (SO4(2-) -NO3-) and marine factor (Cl-).

Acid Rain↗

Analyzing twin resemblance in multisymptom data: genetic applications of a latent class model for symptoms of conduct disorder in juvenile boys.

A model based on the latent class model is developed for the effects of genes and environment on multivariate categorical data in twins. The model captures many essential features of dimensional and categorical conceptions of complex behavioral phenotypes and can include, as special cases, a variety of major locus models including those that allow for etiological heterogeneity, differential sensitivity of latent classes to measured covariates, and genotype x environment interaction (G x E). Many features of the model are illustrated by an application to ratings on eight items relating to conduct disorder selected from the Rutter Parent Questionnaire (RPQ). Mothers rated their 8- to 16-year-old male twin offspring [174 monozygotic (MZ) and 164 dizygotic (DZ) pairs]. The impact of age on the frequency of reported symptoms was relatively slight. Preliminary latent class analysis suggests that four classes are required to explain the reported behavioral profiles of the individual twins. A more detailed analysis of the pairwise response profiles reveals a significant association between twins for membership of latent classes and that the association is greater in MZ than DZ twins, suggesting that genetic factors played a significant role in class membership. Further analysis shows that the frequencies of MZ pairs discordant for membership of some latent classes are close to zero, while others are definitely not zero. One possible explanation of this finding is that the items reflect underlying etiological heterogeneity, with some response profiles reflecting genetic categories and others revealing a latent environmental risk factor. We explore two "four-class" models for etiological heterogeneity which make different assumptions about the way in which genes and environment interact to produce complex disease phenotypes. The first model allows for genetic heterogeneity that is expressed only in individuals exposed to a high-risk ("predisposing") environment. The second model allows the environment to differentiate two forms of the disorder in individuals of high genetic risk. The first model fits better than the second, but neither fits as well as the general model for four latent classes associated in twins. The results suggest that a single-locus/two-allele model cannot fit the data on these eight items even when we allow for etiological heterogeneity. The pattern of endorsement probabilities associated with each of the four classes precludes a simple "unidimensional" model for the latent process underlying variation in symptom profile in this population. The extension of the approach to larger pedigrees and to linkage analysis is briefly considered.

Adolescent↗

Identification of latent variables in a semantic odor profile database using principal component analysis.

Many classifications of odors have been proposed, but none of them have yet gained wide acceptance. Odor sensation is usually described by means of odor character descriptors. If these semantic profiles are obtained for a large diversity of compounds, the resulting database can be considered representative of odor perception space. Few of these comprehensive databases are publicly available, being a valuable source of information for fragrance research. Their statistical analysis has revealed that the underlying structure of odor space is high dimensional and not governed by a few primary odors. In a new effort to study the underlying sensory dimensions of the multivariate olfactory perception space, we have applied principal component analysis to a database of 881 perfume materials with semantic profiles comprising 82 odor descriptors. The relationships identified between the descriptors are consistent with those reported in similar studies and have allowed their classification into 17 odor classes.

Cluster Analysis↗

A comparison of the latent class structure of cannabis problems among adult men and women who have used cannabis repeatedly.

BACKGROUND: Little empirical evidence exists to determine if there are alternative classification schemes for cannabis abuse and dependence beyond the definitions provided by Diagnostic and Statistical Manual (DSM) criteria. Current evidence is not conclusive regarding gender differences for cannabis use, abuse and dependence. It is not known if symptom profiles differ by gender. METHODS: Latent class analysis (LCA) was used to assess whether cannabis abuse and dependence symptom patterns suggest a severity spectrum or distinct subtypes and to test whether symptom patterns differ by gender. Data from 3312 men and 2509 women in the National Longitudinal Alcohol Epidemiologic Survey (NLAES) who had used cannabis 12 + times life-time were included in the present analyses. The comparability of the solutions for men and women was examined through likelihood ratio chi(2) tests. RESULTS: Based on the Bayesian information criterion and interpretability, a four-class solution was selected, and the classes were labeled as 'unaffected/mild hazardous use', 'hazardous use/abuse', 'abuse/moderate dependence' and 'severe abuse/dependence'. The solutions were generally suggestive of a severity spectrum. Compared to men, women were more likely to be in the 'unaffected/mild hazardous use' class and less likely to be in the 'abuse/moderate dependence' or 'severe abuse/dependence' classes. The results were generally similar for men and women. However, men had consistently and substantially higher endorsements of hazardous use than women, women in the 'abuse/moderate dependence' class had moderately higher rates for four dependence symptoms, and women in two of the classes were more likely to endorse withdrawal. CONCLUSION: Our findings generally support the severity dimension for DSM-IV cannabis abuse and dependence symptomatology for both men and women. While our results indicate that public health messages may have generic and not gender-specific content, treatment providers should focus more effort on reducing hazardous use in men and alleviating withdrawal in women.

Adolescent↗

Evaluation of ADHD typology in three contrasting samples: a latent class approach.

OBJECTIVE: To identify subtypes of attention-deficit/hyperactivity disorder (ADHD) and characterize them as either categorical or continuous; to investigate familial resemblance for ADHD among sibling pairs; and to test the robustness of all results by using contrasting data sets. METHOD: Latent class analysis was applied to the ADHD symptom profiles obtained from parents or best informant about their offspring in 3 samples: a population-based set of female adolescent twins (724 monozygotic pairs, 594 dizygotic pairs) and male (N = 425) and female (N = 430) child and adolescent offspring ascertained from high-risk alcoholic families. RESULTS: Latent class analysis revealed 2 categories of clinically significant ADHD which were replicated in all 3 study groups: a subtype with high endorsements of ADHD inattention symptoms and a second combined type with high endorsements of both inattention and hyperactivity-impulsivity items. Both appeared to be continuous across all 3 data groups. The high-risk families contained a class in which members heavily endorsed the ADHD "fidget" item but not other ADHD items. A large proportion of the monozygotic sibs (80%) versus a smaller proportion of dizygotic sibs (52%) were assigned to the same latent class. Among the high-risk children and adolescents, 51% of the female and 41% of the male siblings were concordant for class membership. CONCLUSIONS: The pattern of latent classes suggested that ADHD consists of an inattentive and a combined subtype, within each of which lies a dimensional domain. These analyses further support that genetic factors are significant determinants of latent class membership.

Adolescent↗