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K Schmeck

Publications and source records attributed to K Schmeck.

14 recordsLinked to original sources
PubMed2004

Platelet 5-HT uptake in boys with conduct disorder.

Dysregulation of serotonergic function has been found to be associated with aggression in animals, human adults and adolescents. However, studies with children have shown conflicting results. The objective of this study was to investigate whether the kinetic characteristics (Vmax and Km) of 5-HT uptake in platelets are different in children with the diagnosis of conduct disorder according to ICD-10 and healthy age-matched controls. In addition to the standardized assessment of general psychopathology, methods assessing narrowband aggressive symptoms (Child Behavior Checklist) and emotional reactivity to an experimentally induced provocation (Taylor's competitive reaction time task) were used in both groups. We found a trend for a lower mean Vmax of platelet 5-HT uptake in 14 conduct-disordered boys compared with healthy controls (n=15). If, however, 2 patients with a low degree of aggression and emotional reactivity were excluded, the difference became significant (mean=4.27, SD=3.49 in patients and mean=8.45, SD=4.63 in controls). A significant negative correlation was found between parent-rated aggression scores and Vmax (r=-0.41, p < 0.05, n=29). These data suggest that dysfunction of 5-HT transport mechanisms might be associated with specific behavioral symptoms in conduct-disordered children.

Adolescent↗
PubMed2001

Discriminant validity of the child behaviour checklist CBCL-4/18 in German samples.

This study examined the discriminant validity of the German version of CBCL in two large samples of referred and non-referred children and adolescents which were matched for age, sex and socio-economic status. The combined sample that was used for statistical analysis consists of 2,058 referred and 2,058 non-referred boys and girls between 4 and 18 years of age (mean age: referred boys= 10.9 years, non-referred boys = 10.9 years, referred girls=11.3 years, non-referred girls=11.1 years). Referral status was used as validity criterion. Statistical procedures included Odds Ratios, Total Predictive Values, ROC analyses and discriminant analyses. Results indicated that the discriminant validity of the German version of CBCL is comparable to the original English version. With the use of CBCL Total Problem Score as predictor (cut-off T > or = 60) 83.8% of children and adolescents could correctly be classified (sensitivity 83.6%, specificity 83.9%). Symptoms of the "Attention Problems Scale" show the highest discriminative power to distinguish between disturbed and undisturbed children and adolescents.

Adolescent↗
PubMed2000

[Utilization of psychological tests for diagnosis in German child and adolescent psychiatry: results of a survey].

92 inpatient and outpatient child and adolescent psychiatric institutions all over Germany were surveyed on practice and attitude towards psychological tests. Leading psychologists were contacted by mail and given a 15 item questionnaire. All institutions reported keeping at least a small test-inventory and using psychological tests in diagnostics. Half of the clinics carried out individual tests obligatory in the routine. Additionally, one third applied self-constructed instruments, which in the minority of cases had been psychometrically investigated or published. Computer-aided testing was established in one third of the institutions. Colleagues, test-compendia, scientific journals and the internet are quite often consulted for test-information. Intelligence measures are the most frequently administered test in child and adolescent psychiatry, while structured interviews are applied rarely. Among the highly frequent used individual tests were the Wechsler-Intelligence-Scales for children and adults, the CFT-scales, the projective Sceno-test and the d2-attention endurance test. One forth of the surveyed clinics reported refusal of individual or groups of tests, including projective and cognitive assessments. Thereby, ethic aspects were never mentioned as a reason for rejection. A range of diagnosticians reported to miss adequate measures for diverse constructs, e.g. learning disabilities. Furthermore, new norms and up-dates for regularly used instruments were often demanded. Some single survey-results also give reason for critically reviewing aspects of test-usage in German child and adolescent psychiatry.

Adolescent↗
PubMed1999

Intensity dependence of auditory evoked potentials (AEPs) as biological marker for cerebral serotonin levels: effects of tryptophan depletion in healthy subjects.

RATIONALE: The intensity dependence of the auditory evoked potentials (AEP) has been suggested to be a specific biological marker of central serotonergic activity. OBJECTIVE: While previous studies used circumstantial evidence to support this hypothesis, we manipulated (decreased) cerebral levels of serotonin directly by using tryptophan depletion. METHODS: Twelve healthy young subjects were investigated using placebo and two different amino acid mixtures in a double blind cross over design on three different occasions. AEPs recorded during tryptophan depletion were analyzed by dipole analysis and regional sources using methods published in the literature. RESULTS: For none of the mixtures a significant effect of tryptophan depletion was found. There was a trend towards reduced intensity dependency after tryptophan depletion, especially in the right hemisphere. This reduction correlated with the amount of reduced tryptophan in plasma. CONCLUSIONS: The results indicate, in contrast to earlier indirect studies, that the intensity dependence of AEPs is not a specific marker of central serotonergic activity.

Adult↗
PubMed1999

[Brief report of working group OPD-CA (children and adolescents) Axis IV: structural standard].

Apart from the structural differentiation of the body and its functions, the enlargement of the child's repertoire of possibilities to make experiences and to act is a manifestation of the development of the child's psychic structure which, advancing in years, may be considered as a treasure of all the experiences one has made with oneself, with the world and with the others. Structure will develop along with the interactional experiences with the world around us and becomes manifest in one's behaviour which may be witnessed and observed. The description of the psychic structure comprises three dimensions (perception of the self and of the objects, control, communication and bonding) which will be described by certain capabilities and will be assessed with the help of an anchoring example typical for each age which serves the purpose of clinical illustration. The adaptational achievement may then be assessed on the basis of a structural standard independent of age and may be ranged on a structural level. It appears that the exemplary description of different scopes of tasks typically to be performed at certain ages which serves as a basis for the assessment of the adaptational competence during childhood and adolescence seems to be a good policy. The purpose of our studies is the development of a valid instrument which is easy to handle in practice and which has a high interrater-reliability.

Adolescent↗
PubMed1998

[Incidence of psychiatric symptoms and somatic complaints in 4- to 10-year-old children in Germany as judged by parents--a comparison of norm-oriented and criteria-oriented models].

OBJECTIVES: To analyze the frequency of behavioral/emotional problems and somatic complaints of children aged four to ten as rated by their parents. METHOD: The analysis is based on the PAK-KID study on behavioural and emotional problems and psychosocial competencies of children and adolescents in Germany. In a nationally representative sample of N = 1030 children aged four to ten years the parents rated their child using the Child Behavior Checklist. RESULTS: The prevalence rates of the symptoms are presented. Additionally global prevalence rates based on three different models were calculated and compared. They range from 13.1% to 28.3%. The issues of defining cutoffs necessary for the calculation of prevalence rates are discussed.

Affective Symptoms↗
PubMed1997

[The value of different sources of information in evaluating psychiatric disorders in adolescence--a comparison of parental judgment and self-assessment by adolescents].

Data from the national representative epidemiologic survey (PAK-KID-study) assessed by the German versions of Achenbach'S Child Behavior Checklist and Youth Self-Report of N = 1757 parents and their children aged 11 to 18 years are compared by using the corresponding Cross-Informant-Scales. On all problem scales adolescents report more problems than parents. For some scales the differences between girls and their parents are higher than between boys and their parents (social withdrawal, somatic complaints, anxious/depressed, attention problems, internalizing and total score). Averaged Pearson correlations of the eight subscales are in a moderate rage (r < 0.50). For all problem scales an agreement of 30% in the area of high problems (> PR95) is found. If one informant scores above PR95 the Relative Risk of the other one scoring in this range too is significantly higher than one for nearly all scales.

Adolescent↗
PubMed1997

[Mental disturbances in children and adolescents in Germany. Results of a representative study:age,gender and rater effects].

METHOD: A study on behavioral and emotional problems and competence in children and adolescents in Germany (PAK-KID study) is described. It is the first nationwide representative survey of this kind of children and adolescents aged 4 to 18 years in Germany. For children aged 4 to 10 years the parents completed the German version of Achenbach's Child Behavior Checklist (CBCL 4-18) developed by the Arbeitsgruppe Deutsche Child Behavior Checklist. Children and adolescents aged 11 years and older filled out the German version of the Youth Self-Report that is part of Achenbach's CBCL in addition to the parents completing the German version of the CBCL. A total of 2856 parent questionnaires and 1798 self-report questionnaires completed by children and adolescents were analyzed. RESULTS: The sample was representative with respect to the main sociodemographic variables. On all problem scales children and adolescents aged 11 to 18 years reported significantly more problems than their parents did. The frequency of internalizing problems (social withdrawal, somatic complaints, anxiety/depression) and delinquent behavior of children and adolescents reported by parents increased with the children's age, whereas aggressive behavior and attention problems decreased with age. Girls reported significantly more problems than boys on all internalizing scales of the Youth Self-Report. The effect was not totally replicated in the parent reports. In the parent reports, boys had more attention problems and more aggressive and delinquent behavior than girls.

Adolescent↗
PubMed1996

[Behavioral symptoms of children and adolescents in Germany, the Netherlands and USA. A cross-cultural study with the Child Behavior Checklist].

The goal of the study was a cross-cultural comparison of the parent ratings of behavior problems of children and adolescents aged 4-18 years in Germany, The Netherlands and the United States using the Child Behavior Checklist (CBCL). The analyses were undertaken in a German community sample (n = 1622) and a Dutch community sample (n = 2076). The results were compared with the data published by Achenbach for the national US sample. The analyses were based on the scales of the 1991 CBCL version and were performed for four age and sex groups (4- to 11-year-old boys/girls and 12- to 18-year-old boys/girls). In general, relatively minor differences could be detected between the three random samples. The range in the different samples was between -0.04 and 0.35, which is in line with other cross-cultural analyses using the CBCL. As long as no representative norms for Germany are available, the American norms can serve as an orientation for German studies using the CBCL.

Adolescent↗
PubMed1994

[Reliability and factorial validity of the Child Behavior Checklist--an analysis of a clinical and field sample].

The purpose of this study was to assess the reliability (internal consistency), the correlations of the scale scores and the factorial validity of the German version of the Child Behavior Checklist (CBCL). The analyses were performed in a sample of patients at two child and adolescent psychiatric facilities (N = 1653) and in a community sample (N = 1622). The analyses were based on the 1991 American version of the CBCL. The internal consistency of most of the scales was good to excellent (rtt > .80). The reliability of the scales "Withdrawn", "Somatic complaints" and "Social Problems" was not completely satisfactory (rtt > .70). The reliability of the syndrome scales "Thought Problems" and "Sex Problems" and the Competence Scales was unsatisfactory (rtt < .70). The internal consistency of the syndrome scales in the German and American samples was very similar. The correlations between the scales were predominantly in the lower range, with some in a medium range (rtt > .50). Factor analyses in the clinical sample confirmed that the syndrome scales had been well-designed. With the exception of the scales "Social Problems" and "Withdrawn", where the items have loadings on a common factor, the scales proved to be factorially valid.

Adolescent↗
PubMed1990

[Psychological effects of military low altitude flight practice on children].

In a 2-step epidemiological study child psychiatric disorders, psychophysiological reactions and psychosocial stressors of 376 children aged 4 to 16 were recorded in two regions of Westphalia (West-Germany) with different frequencies of military low-level flights. No essential impairment of the children's health was found. However, below a clinical level we noticed significantly higher anxiety syndromescores (and to some extent of depression syndromescores) and a tendency towards higher psychophysiological arousal in the high-noise area along with no differences in psychosocial stressors. Implications of these results and aspects of child-psychiatric assessment instruments' use are discussed.

Adolescent↗
PubMedDate not supplied

Temperament and disruptive behavior disorders.

In several studies on children with conduct disorder, difficult temperament in infancy was one of the major variables in the explanation of later aggressive behavior. According to these studies, subjects with a combination of high novelty seeking, low harm avoidance and low reward dependence (NS high, HA + RD low) should be most at risk for the development of disruptive behavior disorders. The Junior Temperament and Character Inventory was given to a clinical sample of 65 adolescent patients of both sexes with the diagnoses of conduct disorder (with and without attention deficit hyperactivity disorder), emotional disorder (anxiety disorder, obsessive-compulsive disorder, depressive disorder), eating disorder (anorexia, bulimia) or personality disorder (borderline and narcissistic personality disorder). High novelty seeking and low harm avoidance were significantly correlated with externalizing symptoms like aggression and delinquency. In conduct-disordered children and adolescents, we found significantly higher scores of NS compared to the other clinical groups and the normative population, and significantly lower scores of harm avoidance compared to the other clinical groups, but not compared to the normative population. The relative risk of having a conduct disorder was markedly higher in those children and adolescents with elevated scores of novelty seeking.

Adolescent↗