The relationship between psychopathic traits measured by the Youth Psychopathic trait Inventory and psychopathology in a UK sample of conduct disordered boys

The Youth Psychopathy traits Inventory (YPI) is a newly developed self-report measure of psychopathy. There are no studies looking at the validity of this measure in UK samples. We assessed 115 male adolescents (mean age 16.22 years) with DSM-IV conduct disorder on a range of measures including the YPI, Child Behaviour Checklist (CBCL) and the Impulsivity-Venturesomeness-Empathy Questionnaire (IVE). The YPI had showed the expected positive correlations with aggression, delinquency and impulsivity. The YPI was able to identify a "psychopathic-like" subgroup with higher impulsive/aggressive and delinquent scores and lower empathy. The YPI may be of value as a screening tool for cases that require further assessment and evaluation using interview based measures of psychopathic traits.     

Child Protection Service interference in childhood and the relation with mental health problems and delinquency in young adulthood: a latent class analysis study

Background

Most multi-problem young adults (18–27 years old) have been exposed to childhood maltreatment and/or have been involved in juvenile delinquency and, therefore, could have had Child Protection Service (CPS) interference during childhood. The extent to which their childhood problems persist and evolve into young adulthood may differ substantially among cases. This might indicate heterogeneous profiles of CPS risk factors. These profiles may identify combinations of closely interrelated childhood problems which may warrant specific approaches for problem recognition and intervention in clinical practice. The aim of this study was to retrospectively identify distinct statistical classes based on CPS data of multi-problem young adults in The Netherlands and to explore whether these classes were related to current psychological dysfunctioning and delinquent behaviour.

Methods

Age at first CPS interference, numbers and types of investigations, age at first offence, mention of child maltreatment, and family supervision order measures (Dutch: ondertoezichtstelling; OTS) were extracted from the CPS records of 390 multi-problem young adult males aged 18–27 (mean age 21.7). A latent class analysis (LCA) was conducted and one-way analyses of variance and post-hoc t-tests examined whether LCA class membership was related to current self-reported psychological dysfunctioning and delinquent behaviour.

Results

Four latent classes were identified: (1) late CPS/penal investigation group (44.9%), (2) early CPS/multiple investigation group (30.8%), (3) late CPS interference without investigation group (14.6%), and (4) early CPS/family investigation group (9.7%). The early CPS/family investigation group reported the highest mean anxiousness/depression and substance use scores in young adulthood. No differences were found between class membership and current delinquent behaviour.

Conclusions

This study extends the concept that distinct pathways are present in multi-problem young adults who underwent CPS interference in their youth. Insight into the distinct combinations of CPS risk factors in the identified subgroups may guide interventions to tailor their treatment to the specific needs of these children. Specifically, treatment of internalizing problems in children with an early onset of severe family problems and for which CPS interference is carried out should receive priority from both policy makers and clinical practice.

     

Associations between DSM-IV diagnosis,psychiatric symptoms and morning cortisol levels in a community sample of adolescents

Purpose

Dysfunction of the hypothalamic-pituitary-adrenocortical axis (HPA-axis) is implicated in a variety of psychiatric and emotional disorders. In this study, we explore the association between HPA-axis functioning, as measured by morning cortisol, and common psychiatric disorders and symptoms among a community sample of adolescents.

Method

Data from a cross-sectional school-based survey of 501 school pupils, aged 15, were used to establish the strength of association between salivary morning cortisol and both diagnosis of psychiatric disorders and a number of psychiatric symptoms, as measured via a computerised psychiatric interview. Analysis, conducted separately by gender, used multiple regressions, adjusting for relevant confounders.

Results

With one exception (a positive association between conduct disorder symptoms and cortisol among females) there was no association between morning cortisol and psychiatric diagnosis or symptoms. However, there was a significant two-way interaction between gender and conduct symptoms, with females showing a positive and males a negative association between cortisol and conduct symptoms. A further three-way interaction showed that while the association between cortisol and conduct symptoms was negative among males with a few mood disorder symptoms, among females with many mood symptoms it was positive.

Conclusions

Except in relation to conduct symptoms, dysregulation of morning cortisol levels seems unrelated to any psychiatric disorder or symptoms. However, the relationship between cortisol and conduct symptoms is moderated by both gender and mood symptoms. Findings are compatible with the recent work suggesting research should concentrate on the moderated associations between gender, internalising and externalising symptoms and cortisol, rather than any simple relationship.

     

Multidimensional family therapy in adolescents with a cannabis use disorder: long-term effects on delinquency in a randomized controlled trial

Background

Substance use and delinquency are considered to be mutual risk factors. Previous studies have shown that multidimensional family therapy (MDFT) is effective in tackling both conditions on the short term. The current study examines the long-term effects of MDFT on criminal offending.

Methods

109 adolescents with cannabis use disorder and comorbid problem behavior were randomly assigned to either MDFT or cognitive behavioral therapy (CBT). Police arrest data were collected for 6 years: 3 years prior to and 3 years after treatment entry. Using survival analysis and repeated measure General Linear Models (rmGLM), the two treatment groups were compared on number of arrests, type of offence, and severity of offence. Moderator analyses looking at age, disruptive behavior disorders, history of crimes, family functioning, and (severe) cannabis use were conducted (rmGLM).

Results

While police arrest rates increased in the 3 years before treatment, the rates decreased substantially after the start of both treatments. No differences were found between the treatment groups with respect to either time to first offence from the start of the treatment or changes in frequency or severity of offending over time. A treatment effect trend favoring MDFT was found for property offending in the subgroup of adolescents with high baseline-severity of cannabis use.

Conclusions

Across a follow-up period of 3 years, MDFT and CBT were similarly effective in reducing delinquency in adolescents with a cannabis use disorder.Trial registration ISRCTN51014277, Registered 17 March 2010—Retrospectively registered, http://www.isrctn.com/ISRCTN51014277

     

The role of self-esteem in the development of psychiatric problems: a three-year prospective study in a clinical sample of adolescents

Background

Self-esteem is fundamentally linked to mental health, but its’ role in trajectories of psychiatric problems is unclear. In particular, few studies have addressed the role of self-esteem in the development of attention problems. Hence, we examined the role of global self-esteem in the development of symptoms of anxiety/depression and attention problems, simultaneously, in a clinical sample of adolescents while accounting for gender, therapy, and medication.

Methods

Longitudinal data were obtained from a sample of 201 adolescents—aged 13–18—referred to the Department of Child and Adolescent Psychiatry in Trondheim, Norway. In the baseline study, self-esteem, and symptoms of anxiety/depression and attention problems were measured by means of self-report. Participants were reassessed 3 years later, with a participation rate of 77% in the clinical sample.

Results

Analyses showed that high self-esteem at baseline predicted fewer symptoms of both anxiety/depression and attention problems 3 years later after controlling for prior symptom levels, gender, therapy (or not), and medication.

Conclusions

Results highlight the relevance of global self-esteem in the clinical practice, not only with regard to emotional problems, but also to attention problems. Implications for clinicians, parents, and others are discussed.

     

Examining changes in personality disorder and symptomology in an adolescent sample receiving intensive mentalization based treatment: a pilot study

Objective

To examine changes in personality disorders and symptomology and the relation between personality disorder variables and treatment outcomes in an adolescent sample during partial residential mentalization based treatment.

Methods

In a sample of 62 (out of 115) adolescents treated for personality disorders, assessment was done pre- and post-treatment using the Structured Clinical Interview for DSM personality disorders and the Symptom Check List 90.

Results

Significant reductions in personality disorder traits (t = 8.36, p = .000) and symptoms (t = 5.95, p = .000) were found. During pre-treatment, 91.8% (n = 56) of the patients had one or more personality disorders, compared to 35.4% (n = 22) at post-treatment. Symptom reduction was not related to pre-treatment personality disorder variables.

Conclusion

During intensive psychotherapy, personality disorders and symptoms may diminish. Future studies should evaluate whether the outcomes obtained are the result of the treatment given or other factors.

     

Trafficking among youth in conflict with the law in São Paulo,Brazil

Background

Engagement in drug trafficking may place a child or youth at risk for exposure to severe violence, drug abuse, and death. However, little is know about the nature of youth involvement in drug trafficking. The purpose of this study is to describe drug trafficking behaviour of delinquent youth and identify adverse experiences as potential predictors of trafficking.

Methods

Cross-sectional sample of youth (12–17 years of age) incarcerated in detention facilities for delinquent or criminal acts in São Paulo City, Brazil. Structured face-to-face interviews completed with 325 youth (289 boys, 36 girls).

Results

Approximately half of the boys and girls in this sample have had at least some role in drug trafficking prior to incarceration. Though youth who had engaged in drug trafficking activities did not differ on basic socio-demographic variables, they were more likely to have been exposed to a number of adverse experiences. Beyond heavy substance use, no longer attending school, gang involvement, witnessing violence, and easier access to guns, drugs and alcohol remained significantly related to trafficking involvement in the final regression model. Girls experienced a very similar pattern of adverse exposures as boys.

Conclusion

Special efforts may be required for rehabilitation of youth who engage in drug trafficking. Potential targets may include keeping or re-engaging delinquent youth in school for longer periods of time and reducing youth exposure to violence in poor urban communities.

     

Violent interpersonal trauma predicts aggressive thoughts and behaviors towards self and others: findings from the National Comorbidity Survey-Adolescent Supplement

Purpose

The purpose of the current study is to examine the relation between adolescent traumatic event exposure and aggression directed towards the self and others. Theoretical perspectives underscore the particularly pernicious effects of violent traumas intentionally perpetrated by others in terms of negative posttraumatic outcomes. However, a careful comparison of trauma type in relation to aggression has not been done with youth. The current project, therefore, examined differences between youth with a history of violent interpersonal trauma (VIT) compared to those with a non-violent trauma type history in terms of aggressive behavior directed towards others as well as aggressive self-directed thoughts (suicidal ideation).

Method

The sample was drawn from the National Comorbidity Survey-Replication and consisted of 1928 adolescents (M?=?15.4; SD?=?1.47 years), each assigned to one of four age- and gender-matched trauma history groups.

Results

Consistent with hypotheses, among trauma-exposed youth, those who had experienced or witnessed a VIT (compared to those reporting a non-VIT only) evidenced elevated aggression, even after controlling for a number of theoretically relevant covariates (e.g., gender, age, household income, demographic factors).

Conclusion

Results indicate that youth with a history of VIT may be at unique risk for experiencing aggression directed towards others and the self compared to those without this specific trauma history. This is important because trauma type is an easily assessed indicator of potentially elevated risk for these types of deleterious outcomes. Findings are situated in a research agenda aimed at continuing to refine our understanding of the link between interpersonal trauma and aggression.

     

Deliberate self-harm among adolescent psychiatric outpatients in Singapore: prevalence,nature and risk factors

Background

Deliberate self-harm (DSH) is a prominent mental health concern among adolescents. Few studies have examined adolescent DSH in non-Western countries. This study examines the prevalence, types and associated risk factors of DSH in a clinical sample of adolescents in Singapore.

Methods

Using a retrospective review of medical records, demographic and clinical data were obtained from 398 consecutive adolescent psychiatric outpatients (mean age?=?17.5?±?1.4 years, range?=?13–19 years) who presented at Changi General Hospital from 2013 to 2015.

Results

23.1% (n?=?92) of adolescents engaged in at least one type of DSH. Cutting was the most common type of DSH reported. Females were three times more likely to engage in DSH than males. DSH was positively associated with female gender (odds ratio [OR] 5.03), depressive disorders (OR 2.45), alcohol use (OR 3.49) and forensic history (OR 3.66), but not with smoking behaviour, living arrangement, parental marital status, past abuse or family history of psychiatric illness.

Conclusion

Interventions targeting adolescent DSH should also alleviate depressive symptoms, alcohol use and delinquent behaviours.

     

Negative association between plasma cortisol levels and aggression in a high-risk community sample of adolescents

In this study, the association of aggressive behavior and personality traits with plasma cortisol levels was investigated in a high-risk community sample of adolescents. Plasma cortisol levels were collected in 245 fifteen-year-olds (118 males, 127 females) from an epidemiological cohort study of children at risk for psychopathology. Additionally, measures of reactive and proactive aggression, externalizing behavior and callous-unemotional together with impulsive personality features were assessed. Both subtypes of aggression as well as delinquent behavior and impulsive personality traits showed significant negative correlations with plasma cortisol levels. This association was observed in males, but not in females. In both gender groups, callous-unemotional traits were unrelated to plasma cortisol levels. This result suggests that the association between cortisol levels and aggression in adolescents is mediated rather by impulsivity than by unemotional or psychopathic traits.     

The association between ethnic background and characteristics of first mental health treatment for psychotic disorders in the Netherlands between 2001 and 2005

Purpose

To test the hypothesis that ethnic minority status of patients is associated with specific psychotic disorder treatment characteristics.

Methods

Longitudinal data (2001–2005) were extracted from a nationwide psychiatric case register in the Netherlands. The sample consisted of 30,655 episodes of mental health treatment for 23,122 patients with psychotic disorders. Information was available about waiting time and treatment duration, source of referral, occurrence of crisis contacts, admittance to clinical care and compulsory admissions. In addition, information was available about ethnicity (based on country of birth), gender, age and marital status. Results were calculated for ethnic and gender groups separately. In addition, a number of multivariate regression analyses were conducted to correct for differences in age and marital status.

Results

There was substantial variation between ethnic minority and gender groups in relation to the treatment characteristics. Compared with a Dutch ethnic background, ethnic minority background was generally associated with less waiting time, and more police referrals, crisis contacts, admittance to clinical care and compulsory admission, but shorter treatment duration. Characteristics appeared to be least favorable in episodes that involved male patients with Antillean and Surinamese backgrounds, whereas episodes were quite similar for ethnic Dutch and Turkish patients.

Conclusions

Characteristics of mental health treatment for psychosis in the Netherlands are different for ethnic minority patient groups than for patients with an ethnic Dutch background. However, there were substantial differences between ethnic minority groups.

     

With friends like these…: Peer delinquency influences across age cohorts on smoking, alcohol and illegal substance use

Background

Discussions and debate about youth smoking, alcohol use, and illegal substance use (collectively referred to as youth substance use) continue to receive wide attention among researchers, policymakers, and the general public. Previous research has suggested that peer delinquency is a particularly strong correlate of youth substance use. The current study focuses on the influence of delinquent peers on substance use, and how peer delinquency influences change across age cohorts of youth.

Method

The current study examines multiple correlates for youth substance use in a sample of 8,256 youth (mean age 14), with the goal of identifying the influence of delinquent peers across age cohorts while controlling for other correlates. Data was collected from the Ohio version of the Youth Risk Behavior Surveillance System (YRBSS) developed by the Centers for Disease Control.

Results

Results from multiple regression analyses identified peer delinquency as the strongest correlate of youth substance use even when other relevant factors related to family, neighborhood, and media use were controlled. Correlations between peer delinquency and substance use behavior increased across age cohorts and for individuals who first used in middle teen years (13-16) irrespective of current age.

Interpretation

Age appears to be a moderating factor regarding the correlation between peer delinquency and youth substance abuse. Primary and secondary prevention and intervention strategies that focus on peers are potentially more likely to reduce youth substance use and improve peer relationships than those focused on other areas such as schools or media.     

Therapieabbruch als Prädiktor erneuter Straftaten

Background

Recidivism rates in substance-addicted patients placed in institutions according to §64 of the German legal code are approximately 50%, 3 years after discharge from inpatient treatment. The recidivism rates of patients with premature termination of inpatient treatment who had then been referred back to prison and were finally discharged into the community are unknown.

Research question

Is premature termination of treatment a risk factor for recidivism?

Methods

Patients released from forensic treatment according to § 64 of the German legal code were followed up for violent and non-violent recidivism. Full data were acquired for Baden-Württemberg patients released in 2010 and 2011 with regular vs. premature termination of treatment.

Results

All measures revealed highly significant group differences: 48% of the patients discharged after subsequent prison sentences recidivated within the first year and 73% within 3 years after discharge. Among recidivists, the severity of offences was much higher (odds ratio > 3.8 each). Regularly discharged patients also re-offended to a remarkable extent (50%).

Discussion

Patients serving prison sentences after unsuccessful forensic treatment are a high-risk group for recidivism. Alternative concepts of clinical and legal treatment of this group should be developed.

     

Mental health burden in a national sample of American Indian and Alaska Native adults: differences between multiple-race and single-race subgroups

Purpose

Research on American Indian and Alaska Native (AIAN) mental health disparities is based largely on either tribal populations or national samples of adults that do not account for multiracial AIANs, even though over 40% of AIANs identify with multiple racial groups. The present investigation extends this research by assessing mental health status in a national sample of multiracial AIAN adults relative to adults who identify exclusively as either AIAN or White.

Methods

2012 BRFSS data were used to conduct multinomial logistic regression analyses comparing mental health outcomes among respondents who identified as either AIAN and one or more other races (AIAN-MR), AIAN-Single Race (AIAN-SR), or White-SR.

Results

After demographic adjustment, the AIAN-MR group reported a higher lifetime prevalence of diagnosed depressive disorder, more days of poor mental health, and more frequent mental distress compared to both the AIAN-SR and White-SR groups. AIAN-MR individuals also had higher levels of Kessler 6 (K6) non-specific psychological distress compared to White-SR individuals but not AIAN-SR adults. Differences between AIAN-SR and White-SR adults were found in days of poor mental health, frequent mental distress, and total K6 scores.

Conclusions

These findings help gauge the magnitude of mental health disparities in the U.S. AIAN population and pinpoint AIAN subgroups for whom mental health is particularly problematic. As such, they raise concerns about restrictions that limit the identification of national survey respondents who report multiple race designations. Such restrictions will thwart efforts to understand the causal mechanisms and pathways leading to mental distress among AIAN individuals.

     

A compromise solution between overlapping and overlooking DSM personality disorders in Chinese psychiatric practice

Objective

This study aimed to examine the overlaps between the Diagnostic and Statistical Manual-5 (DSM-5) Personality Disorders (PDs) in a high-risk clinical population and to explore a transitional model for implementing DSM-5 PDs.

Method

A sample population of 982 outpatients with at least one diagnosed PD was selected from 3,075 outpatients of the Shanghai Mental Health Center. The diagnostic process comprised of a personality diagnostic questionnaire and a structured clinical interview.

Results

685 (22.3%) patients were diagnosed with at least one of six PDs (antisocial, avoidant, borderline, narcissistic, obsessive–compulsive, and schizotypal) under the alternative DSM-5 model for personality disorders proposed in Section III of the DSM-5. Nearly 20.3% of the subjects with PD met criteria for at least two PDs (of the 685 PD patients/6 PD model). Cluster and principal component analyses suggest a transitional model for the 7 specific PD categories (among the 722 PD patients, the overlapping rate was 24.1%) will be more appropriate for PD diagnosis in China.

Conclusions

Using the simplified PD categories in the alternative DSM-5 model for personality disorders will reduce the overlaps in PD diagnoses in Chinese psychiatric practice, and should be preferred over the DSM-5 PD diagnostic system.

     

Addressing the Needs of Preschool Children in the Context of Disasters and Terrorism: Clinical Pictures and Moderating Factors

Purpose of Review

This paper surveys the existent theoretical and research literature regarding the needs of preschool children in the context of disasters and terrorism with the aim of understanding (a) the consequences of such events for young children and (b) the main moderating variables influencing the event-consequence association to learn how to enhance their resilience.

Recent Findings

Consequences include a variety of emotional, behavioral, and biological outcomes. Implications for refugee children are discussed. Main moderating variables were mother’s sensitivity and mother’s PTSD symptoms.

Summary

Exposure to disasters and terrorism may have severe effects on the mental health and development among preschool children. Future research should explore the implications of different levels of exposure and the effects of moderating psychosocial and biological variables, including the parent-child triad, on the event-consequence relationship.

     

The role of feared possible selves in the relationship between peer influence and delinquency

This study explores the impact of a feared delinquent possible self on the relationship between exposure to negative peer behaviors and violent and non-violent self-reported delinquency. Previous research strongly supports that deviant peers influence adolescents' delinquent behavior. Yet, few studies have explored intrapersonal factors that may moderate this influence. Possible selves include what one hopes, expects and fears becoming and are believed to motivate behavior. Thus, it was hypothesized that adolescents who were exposed to deviant peers and also feared engaging in delinquency would be more likely to self-report delinquency. Seventh grade students (n = 176) identified feared possible selves in the future, their exposure to negative peer behavior and self-reported violent and non-violent delinquent behavior. Findings suggest that exposure to negative peer behavior is associated with self-reported delinquent behavior. For violent behavior, possessing a feared delinquent possible self moderates this relationship. Implications and suggestions for future research are discussed.     

Differences by Veteran/civilian status and gender in associations between childhood adversity and alcohol and drug use disorders

Purpose

To examine differences by US military Veteran status and gender in associations between childhood adversity and DSM-5 lifetime alcohol and drug use disorders (AUD/DUD).

Methods

We analyzed nationally representative data from 3119 Veterans (n?=?379 women; n?=?2740 men) and 33,182 civilians (n?=?20,066 women; n?=?13,116 men) as provided by the 2012–2013 National Epidemiologic Survey on Alcohol and Related Conditions (NESARC-III). We used weighted multinomial logistic regression, tested interaction terms, and calculated predicted probabilities by Veteran status and gender, controlling for covariates. To test which specific moderation contrasts were statistically significant, we conducted pairwise comparisons.

Results

Among civilians, women had lower AUD and DUD prevalence than men; however, with more childhood adversity, this gender gap narrowed for AUD and widened for DUD. Among Veterans, in contrast, similar proportions of women and men had AUD and DUD; with more childhood adversity, AUD-predicted probability among men surpassed that of women. Childhood adversity elevated AUD probability among civilian women to levels exhibited by Veteran women. Among men, Veterans with more childhood adversity were more likely than civilians to have AUD, and less likely to have DUD.

Conclusions

Childhood adversity alters the gender gap in AUD and DUD risk, and in ways that are different for Veterans compared with civilians. Department of Defense, Veterans Affairs, and community health centers can prevent and ameliorate the harmful effects of childhood adversity by adapting existing behavioral health efforts to be trauma informed, Veteran sensitive, and gender tailored.

     

The interplay of psychosis and victimisation across the life course: a prospective study in the general population

Purpose

Psychosis has been associated with adult victimisation. However, it remains unclear whether psychosis predicts incident adult victimisation, or whether adult victimisation predicts incident psychosis. Furthermore, a moderating effect of childhood victimisation on the association between psychosis and adult victimisation has not been investigated.

Methods

The longitudinal association between baseline psychotic experiences and six-year incidence of adult victimisation was assessed in a prospective general population cohort of 6646 adults using logistic regression analysis. The association between baseline adult victimisation and six-year incidence of psychotic experiences was examined as well. Furthermore, the moderating effect of childhood victimisation on these bidirectional associations was analysed.

Results

Psychotic experiences and childhood victimisation were both associated with an increased risk of incident adult victimisation. However, this was through competing pathways, as suggested by a negative interaction between psychotic experiences and childhood victimisation. Baseline adult victimisation and childhood victimisation both independently increased the risk of incident psychotic experiences, but there was no interaction between adult victimisation and childhood victimisation.

Conclusions

Psychosis and victimisation are interconnected throughout the life course. Childhood victimisation is connected to psychosis through two pathways: one direct and one indirect through adult victimisation. In individuals without childhood victimisation, psychosis and adult victimisation bidirectionally impact on each other.

     

Parenting style and mental disorders in a nationally representative sample of US adolescents

Purpose

We examined associations between parenting style and past-year mental disorders in a nationally representative cross-sectional survey of US adolescents and whether the associations differed by adolescent demographic characteristics.

Methods

The sample included 6483 adolescents aged 13–18 years who were interviewed for a full range of DSM-IV mental disorders. Parenting style was assessed by adolescent-reported maternal and paternal care and control using items from the Parental Bonding Instrument. We controlled for socio-demographics, parental history of mental disorders, stressful life events, sexual violence, inter-parental conflict, and household composition. We also tested for two-way interactions between parental care and control and adolescent age, sex, and race/ethnicity.

Results

In adjusted models, high maternal care was associated with lower odds of depressive, eating, and behavioral disorders, and high maternal control was associated with greater odds of depressive, anxiety, eating, and behavioral disorders. High paternal care was associated with lower odds of social phobia and alcohol abuse/dependence. High paternal control was associated with greater odds of agoraphobia and alcohol abuse/dependence but with lower odds of attention-deficit/hyperactivity disorder. Associations of maternal and paternal control with anxiety disorders and substance abuse/dependence differed by sex. High paternal care was associated with lower odds of anxiety disorders only among Hispanics and non-Hispanic blacks.

Conclusions

Perceived parental care and control were associated with adolescent mental disorders after controlling for multiple potential confounders. Differential patterns of association were found according to adolescent sex and race/ethnicity. Findings have implications for prevention and intervention programs that incorporate familial contextual factors.