Nonaggressive Group Research Articles

The Effects of Early Aggressive Rehabilitation on Outcomes After Anterior Cruciate Ligament Reconstruction Using Autologous Hamstring Tendon: A Randomized Clinical Trial

Prospective randomized clinical trial. Thirty-six patients who had a primary anterior cruciate ligament reconstruction (ACL-R) with a semitendinosus-gracilis (STG) autograft from a single orthopedic surgeon were prospectively randomized into 2 groups. Nineteen patients were randomized to the aggressive group (53% male, mean age 30.1 + 10.5 y) and 17 to the nonaggressive group (88% male, mean age 33.1 + 10.9 y). Impairment measures of anteroposterior (A-P) knee laxity, range of motion (ROM), and peak isometric force (PIF) values were obtained 12 wk postoperatively. Subjective response to the International Knee Documentation Committee knee form (IKDC) was collected 1, 12, and 24 wk postoperatively. One-way ANOVA was used to analyze differences between groups at 12 wk for A-P knee laxity, ROM, and PIF. Differences between the groups for the IKDC scores were determined using 1-way ANOVA with repeated measures 1, 12, and 24 wk postoperatively. Bonferroni adjustment was used for multiple comparisons. There were no differences between the groups for the baseline characteristics (P > .05). There was no difference found between the groups in respect to A-P knee laxity, ROM, or PIF at 12 wk (P > .05). Further analysis also showed no significant differences in the IKDC scores between groups at 12 or 24 wk (P > .05). No differences were found between early aggressive and nonaggressive rehabilitation after an isolated ACL-R using STG autografts for the primary outcomes of A-P knee laxity and subjective IKDC score. In addition, no differences were observed for secondary outcomes between groups for differences in ROM and PIF values.

The relationship among the aggressive behavior, hostile attribution bias and childhood trauma in schizophrenic patients

Objective To explore the relationship among the aggressive behavior, hostile attribution bias and childhood trauma in schizophrenic patients. Methods 135 schizophrenic patients were tested with Modified Overt Aggression Scale (MOAS), the Chinese-version of the Ambiguous Intentions Hostility Questionnaire (AIHQ-C) and Childhood Trauma Questionnaire (CTQ). According to the score of the MOAS, the patients were divided into the aggressive group (n=58) and the non-aggressive group (n=77). The hostile attribution bias and the childhood trauma were compared between the two groups, and correlation and hierarchical regression analysis were used to investigate the relationships of the variables. Results Compared with the non-aggressive patients, the aggressive patients had significantly higher AIHQ-C total hostility bias score (6.27±1.20 vs 5.90±0.97, P<0.05), total blame bias score (8.04±1.97 vs 6.91±2.10, P<0.01) and total aggression bias score (6.17±1.02 vs 5.59±1.04, P<0.01). Correlation analysis showed that the MOAS score, AIHQ scores and the total score of CTQ were significantly positively correlated with each other (r=0.171~0.350, P<0.05~0.01). Regression analysis indicated the hostile attribution bias directly predicted the aggressive behavior(β=0.342, P<0.05)and completely mediated the relationship between the childhood trauma and the aggressive behavior. Conclusion The aggressive behavior in schizophrenic patients is associated with the experience of childhood trauma and the attribution style. The childhood trauma indirectly influences the aggressive behavior by the mediating of the hostile attribution bias. Key words: Schizophrenia; Aggressive behavior; Hostility; Attribution; Childhood Trauma

Study on the event-related potentials P300 of schizophrenic patients with aggressive or violent behaviors

Objective To explore the electrophysiological mechanisms of the schizophrenic patients with aggressive or violent behaviors. Methods Access the aggressive behaviors of schizophrenic patients being treated in hospitals or clinics with the revised MOAS in accordance with the ICD-10 diagnostic criteria, and sort the qualified patients into two groups: the group of aggressive or violent schizophrenia (Aggressive Group, n=70) and the group of non-aggressive or non-violent schizophrenia (Non-Aggressive Group, n=65); 60 age- and gender-matched healthy people were collected as Healthy Group. P300 tests were carried out on patients in these three groups with the MEB-9200 Nicolet Bravo Instrument by the Nihon Kohden Corporation. Results (1) Latency P3a of the Aggressive Group on Cz point exceeded that of the Non-Aggressive Group (P=0.01), and that of the Non-Aggressive Group exceeded that of the Healthy Group. All these disparities were of statistical significance (P<0.01). Latency P3a of the Aggressive Group on Fz point exceeds that of the Non-Aggressive Group, and that of the Non-Aggressive Group exceeded that of Healthy Group. All these disparities are also of statistical significance(P<0.01). (2)N2′ amplitude of the Aggressive Group on Cz point was higher than those of the Non-Aggressive Group and the Healthy Group. This disparity was of statistical significance(P<0.05) and the disparity between the Non-Aggressive Group and the Healthy Group did not have statistical significance(P=0.985). Conclusion Characteristic electrophysiological changes exist in the event-related potentials P300 of schizophrenic patients with aggressive or violent behaviors. Key words: Schizophrenia; Aggressive or violent behaviors; Event-related potentials

Giant Cell Lesions of the Jaws: Does the Level of Vascularity and Angiogenesis correlate With Behavior?

To compare vascularity and angiogenic activity in aggressive and nonaggressive giant cell lesions (GCLs) of the jaws. This is a retrospective study of 14 GCLs treated at the University of California, San Francisco. Immunohistochemistry was used to determine of the expression of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), CD34, and CD31. VEGF and bFGF expression in giant cells (GCs) and surrounding mononuclear stroma was classified into 1) high immunoreactivity (>50% staining) and 2) low immunoreactivity (<50% staining). CD31- and CD34-stained vessels were counted at 200× magnification. Clinical and radiographic records were reviewed to classify lesions as aggressive or nonaggressive. Of the lesions, 8 were aggressive and 6 were nonaggressive. High VEGF expression was found within the GCs in 4 of 8 aggressive lesions compared with 1 of 6 nonaggressive lesions. The stroma in both groups had low staining. High staining of the GCs for bFGF was found in 6 of 8 aggressive lesions compared with 3 of 6 nonaggressive lesions. The stroma of all aggressive cases showed high expression of bFGF compared with 3 of 6 nonaggressive cases. The aggressive group had a mean of 20.1 ± 5.4 vessels/high-powered field (hpf) stained for CD31 compared with 11.5 ± 5.6 vessels/hpf in the nonaggressive group. The aggressive group had 24.6 ± 7.0 vessels/hpf stained with CD34 compared with 18.5 ± 4.0 vessels/hpf in the nonaggressive group. The vascularity and level of angiogenesis within aggressive GCLs are higher than those in nonaggressive lesions.

The correlates of aggression in people with acquired brain injury: A preliminary retrospective study

Primary objective: To identify correlates of aggressive behaviours in patients with acquired brain injury (ABI).Methods and procedures: During a 16 month period, patients who had ABI and who had been aggressive during hospitalization (n = 32) were identified by hospital staff. A comprehensive chart review of these patients was completed. Results were compared against results of a matched patient sample who had not been aggressive (32).Main outcomes and results: Five variables which were significantly correlated with aggression were entered into a standard logistic regression. The model explained 61.4% of the total variance and successfully predicted 87.5% of the non-aggressive group and 78.1% of the aggressive group. The overall correct prediction rate was 82.8%. Of the five variables, four were found to significantly contribute to the predictive ability of the model: An education of 10 years or less, a history of aggression, dependence on staff for assistance with activities of daily living and a hospitalization period of 51 days or more.Conclusions: The results highlight some variables related to aggression by patients with ABI in the hospital environment and can be utilized in staff education and training programmes to increase the awareness of risk factors.

Abstract 2781: Genetic variations in angiogenesis-related genes in prostate cancer aggressiveness

Abstract Prostate cancer is the most common cancer and the second leading cause of cancer death in American men. Clinicians usually face difficulties in distinguishing indolent and aggressive tumors at the time of prostate cancer diagnosis. Thus, there is an urgent need for finding biomarkers to predict prostate cancer prognosis in order to select a suitable treatment plan for prostate cancer patients. Angiogenesis, the development of new blood vessels, has been shown to be associated with Gleason score, tumor stage, progression, metastasis and survival in prostate cancer patients. We used 1,151 prostate cancer cases (492 non-aggressive and 659 aggressive) obtained from the Cancer Genetic Markers of Susceptibility (CGEMS) prostate cancer genome-wide data set. This objective of this study is to evaluate single nucleotide polymorphisms (SNPs) in the angiogenesis-related genes associated with prostate cancer aggressiveness. A total of 2,653 SNPs in 161 angiogenesis-related genes in the nonsex chromosomes were evaluated after excluding two SNPs, which were not followed the Hardy-Weinberg equilibrium in the control group. A patient with a Gleason score &amp;lt; 7 and stage &amp;lt; III was categorized into the non-aggressive group; while a patient with a Gleason score &amp;gt; 7 or stage &amp;gt; III was categorized into the aggressive group. The associations between prostate cancer aggressiveness and individual SNPs with different inheritance models (dominant, recessive, log-additive or genotypic model) were evaluated using logistic regression models. For each SNP, the minimum p-value among all testing inheritance models was selected. A total of 287 SNPs had raw-p values less than 0.05. Of the 287 SNPs, 89 SNPs had FDR q value less than 10%. Because the individual SNP analyses only considered one SNP associated with the outcome, we applied Random Forests (RF) analysis, a machine learning method, to explore important SNPs associated with prostate cancer aggressiveness though SNP-SNP interactions. RF provides the variable importance rank, which takes interactions into consideration. The top two SNPs in the univariate rank are rs1477908 (OR = 0.65, 95%CI=0.52-0.81, p=0.00017, log-additive model) and rs2616488 (OR=0.70, 95%CI=0.58-0.85, p=0.0002, log-additive model). Both SNPs were in the MMP16 gene and are also in the top one and five in the RF rank, respectively. Among top 10 SNPs in the RF ranking, 3 SNPs were in the FBLN5 gene. The RF (univariate) rank for these three SNPs (rs2498852, rs929608, and rs2052204) were 3 (8), 4 (31) and 9 (72). These data show that the impact of the SNPs in the FBLN5 gene was partially through interactions. Previous studies reported that the MMP16 and FBLN5 have different regulation in prostate cancer. This study suggests variants in angiogenesis-related genes, especially MMP16 and FBLN5, appear to influence prostate cancer aggressiveness. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2781. doi:10.1158/1538-7445.AM2011-2781

Polymorphisms of serotonin transporter gene-linked polymorphic region and aggression behavior in schizophrenia

Objective To explore the association of the polymorphisms of serotonin transporter gene-linked polymorphic region (5-HTTLPR) with aggression behavior in schizophrenia. Methods 195 patients who met the diagnostic criteria for schizophrenia on DSM-IV were recruited and divided into aggressive and non-aggressive groups according to their scores of the Modified Overt Aggression Scale (MOAS). 99 patients who had a total weighted MOAS score of≥ 4 were as aggressive subjects, and the other 96 patients who had a score of zero were as non-aggressive controls. 5-HTTLPR polymorphisms were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. Results The distribution of genotypes or alleles of the 5-HTTLPR polymorphisms did not differ significantly between the two groups (P >0.05), neither after stratification by male and female in both groups (P>0.05). Conclusions 5-HTTLPR polymorphisms are not associated with aggression behavior in schizophrenia. Key words: Aggression behavior; 5-HTTLPR polymorphisms; Schizophrenia

Relationship between Levels of Testosterone and Cortisol in Saliva and Aggressive Behaviors of Adolescents

To explore the endocrinal factors which influence the aggressive behavior of adolescents. The levels of cortisol (CORT), testosterone (T), prolactin (PRL), and growth hormone (GH) in saliva from 20 aggressive students and 20 non-aggressive control students were measured by radioimmunoassay (RIA). The students were matched for their gender, age, grade, stage of pubertal development, and economic status of their families. The salivary T levels were 22.20 +/- 14.50 pg/mL and 19.54 +/- 12.52 pg/mL in aggressive male and female students, 13.20 +/- 6.85 pg/mL and 5.24 +/- 3.03 pg/mL in non-aggressive male and female students (P < 0.05). The male aggressive students had a lower level of CORT in saliva than non-aggressive male students (P < 0.05). There were no significant differences in the salivary levels of PRL or GH between the aggressive and non-aggressive groups. Correlation analysis revealed a negative relationship in male students between the salivary CORT levels and the aggression factor scores of the child behavior checklist (CBCL). In addition, the data also showed a positive relationship between the salivary T levels and the aggression factor scores of CBCL in female students. Multiple linear regression analysis showed that the salivary CORT level was an independent predictive factor for aggressive behaviors in adolescent boys. The higher the CORT level, the less aggressive the boys were. CORT and T levels may play a certain role in adolescent aggressive behaviors.

Aggressive incidents on a psychiatric intensive care unit

Aims and MethodThis study looked at patient aggressive behaviour on an Irish psychiatric intensive care unit, and whether it was related to diagnosis, patient's insight and symptomatology. Each aggressive incident was recorded throughout the patient's stay using the Staff-Observed Aggression Scale.ResultsNinety-nine individuals were admitted to the unit during the study. We recorded 82 aggressive incidents, with most occurring during the daytime and on weekdays. There was no statistical difference in BPRS scores between the aggressive and non-aggressive groups. the aggressive patient group had a lower insight score than the non-aggressive group (P &lt; 0.05) as measured on the Schedule of the Assessment of Insight. However, when gender and verbal aggression only were included in the analysis, the difference in insight was less significant (P=0.07).Clinical ImplicationsAggression is common on a psychiatric intensive care unit. Low levels of insight in patients may increase the risk of aggression.

Rage Attacks and Aggressive Symptoms in Japanese Adolescents with Tourette Syndrome

This study was conducted to explore possible causes of rage attacks as well as clinically significant aggressive symptoms in Japanese adolescents with Tourette syndrome (TS). The subjects included 29 adolescents (23 males, 6 females; mean age: 13.5+/-3.7 years). Eighteen subjects (62.1%) were diagnosed with TS only, 11 (37.9%) with TS and comorbidities, including attention-deficit/hyperactivity disorder and obsessive-compulsive disorder. Parents completed the Child Behavior Checklist. Clinically significant aggressive symptoms were assessed using two pilot tools, the Rage Screen and Questionnaire and the Clinical Rating of Aggression. Thirteen subjects (44.8%) were judged to have clinically significant aggressive symptoms, according to the Clinical Rating of Aggression. Twelve met criteria for recurrent rage attacks, according to the Rage Screen and Questionnaire. Between the 13 aggressive and 16 non-aggressive subjects, no significant differences were found in age, gender, psychiatric comorbidities, or concurrent medication. Child Behavior Checklist ratings to compare 11 aggressive and 12 non-aggressive subjects <16 years of age revealed elevated t-test scores on the anxious/depressed, thought problems, aggressive, internalizing, externalizing subscales, and total scale in the aggressive group versus the non-aggressive group. Rage attacks and clinically significant aggressive symptoms are common problems in Japanese TS youth. Psychiatric morbidity appears associated with impulsive-aggressive symptoms. Treatment implications from these findings need to be explored further.

The introduction history of invasive garden ants in Europe: Integrating genetic, chemical and behavioural approaches

BackgroundThe invasive garden ant, Lasius neglectus, is the most recently detected pest ant and the first known invasive ant able to become established and thrive in the temperate regions of Eurasia. In this study, we aim to reconstruct the invasion history of this ant in Europe analysing 14 populations with three complementary approaches: genetic microsatellite analysis, chemical analysis of cuticular hydrocarbon profiles and behavioural observations of aggression behaviour. We evaluate the relative informative power of the three methodological approaches and estimate both the number of independent introduction events from a yet unknown native range somewhere in the Black Sea area, and the invasive potential of the existing introduced populations.ResultsThree clusters of genetically similar populations were detected, and all but one population had a similar chemical profile. Aggression between populations could be predicted from their genetic and chemical distance, and two major clusters of non-aggressive groups of populations were found. However, populations of L. neglectus did not separate into clear supercolonial associations, as is typical for other invasive ants.ConclusionThe three methodological approaches gave consistent and complementary results. All joint evidence supports the inference that the 14 introduced populations of L. neglectus in Europe likely arose from only very few independent introductions from the native range, and that new infestations were typically started through introductions from other invasive populations. This indicates that existing introduced populations have a very high invasive potential when the ants are inadvertently spread by human transport.

Association Study of MAO-A and DRD4 Genes in Schizophrenic Patients with Aggressive Behavior

Genes involved in dopamine neurotransmission are interesting candidates to be analyzed in schizophrenia and aggressive behavior. Therefore, we analyzed the functional polymorphisms of the dopamine receptor D4 (DRD4) and monoamine oxidase A (MAO-A) genes in a sample of 71 schizophrenic patients assessed with the Overt Aggression Scale to measure aggressive behavior. CLUMP analysis of the DRD4 48-bp repeat-exon III polymorphism in schizophrenic patients showed significant differences between the aggressive behavior and the nonaggressive groups (T1 = 18.77, d.f. = 6, p = 0.0046; T3 = 6.54, p = 0.0195). However, analysis of the promoter polymorphism of the MAO-A gene revealed no significant association between aggressive and nonaggressive patients. Finally, analysis of Overt Aggression Scale dimensions exhibited significant differences for the DRD4 and MAO-A genes. Our preliminary findings suggest that the DRD4 and MAO-A genes may be involved in aggressive schizophrenic patients.

They're Cool: Social Status and Peer Group Supports for Aggressive Boys and Girls

This study examined who among the 526 fourth to sixth graders are nominated as among the coolest kids in their class. There were two questions: (1) Are popular-aggressive (tough) children nominated as cool by a broad spectrum of their peers, or only by a select few? (2) Does variability in children’s cool nominations more closely follow their individual characteristics or group affiliations? Three-level hierarchical linear modeling (nominators in groups in classrooms) tested the study hypotheses. The main finding was that children in aggressive groups nominated tough peers as cool and children in nonaggressive groups nominated popular-nonaggressive (model) peers, regardless of nominators’ individual characteristics or the prominence of their groups across diverse classroom contexts. Girls were proportionately more likely to nominate tough than model boys, but only a minority (less than 25 percent) of relatively aggressive girls nominated any boys as cool. Findings indicate that normative boy and girl peer cultures give broad reputational support to some aggressive children.

Central giant cell granuloma of the jaws: A clinical, radiologic, and histopathologic study of 26 cases

The clinical behavior of central giant cell granuloma (CGCG) of the jaws is variable and difficult to predict. Clinical data and follow-up information of 26 patients with CGCG were analyzed. Histologic features were correlated with the clinical course of the disease. In 16 patients the CGCGs were asymptomatic; 10 lesions presented with aggressive growth, pain, massive swelling, root resorption, cortical perforation, and/or recurrence. These patients were younger and the lesions were larger than in the nonaggressive group. The histomorphometric analysis proved a significant increase in large giant cells, fractional surface area, and mitotic activity in aggressive CGCG lesions. Immunohistologic investigation (Ki-67 and p53 stain) revealed no significant differences. After surgical treatment, 3 patients with aggressive lesions developed a recurrence. The data show that clinical and histomorphometric features may be reliable indicators for the differentiation between aggressive and nonaggressive CGCG. This should be accounted for to improve the individual planning of the treatment and follow-up.

Prognostic Implication of Telomerase Activity in Patients with Brain Tumors

Telomerase adds telomeric repeats to the ends of telomeres to compensate for their progressive loss. A favorable prognosis is associated with low or no telomerase in some tumors. The authors investigated whether telomerase activity is associated with survival of patients with brain tumors. Sixty-two consecutive patients with brain tumors underwent surgery, and their surgical specimens were investigated. The patients were pathologically categorized as group I (aggressive group) and group II (non-aggressive group). Telomerase activity was examined by the telomeric repeat amplification protocol (TRAP) assay. The median time was calculated in association with overall survival and progression-free survival in each group. The significant difference was noted in telomerase activity between high-grade gliomas and low-grade gliomas (p=0.022). Telomerase activity was significantly associated with the median overall survival and progression-free survival in all tumors of the aggressive group. On the other hand, the median overall survival in the non-aggressive group was not dependent on telomerase activity, while the median progression-free survival was. Our data suggests that telomerase is an important prognostic indicator of survival in patients with brain tumors.

Neuroendocrine Hepatic Metastases

The aim of this study was to determine whether aggressive management of neuroendocrine hepatic metastases improves survival. Survival in patients with carcinoid and pancreatic neuroendocrine tumors is significantly better than adenocarcinomas arising from the same organs. However, survival and quality of life are diminished in patients with neuroendocrine hepatic metastases. In recent years, aggressive treatment of hepatic neuroendocrine tumors has been shown to relieve symptoms. Minimal data are available, however, to document improved survival with this approach. The records of patients with carcinoid (n = 84) and pancreatic neuroendocrine tumors (n = 69) managed at our institution from January 1990 through July 2004 were reviewed. Eighty-four patients had malignant tumors, and hepatic metastases were present in 60 of these patients. Of these 60 patients, 23 received no aggressive treatment of their liver metastases, 19 were treated with hepatic resection and/or ablation, and 18 were managed with transarterial chemoembolization (TACE) frequently (n = 11) in addition to resection and/or ablation. These groups did not differ with respect to age, gender, tumor type, or extent of liver involvement. Median and 5-year survival were 20 months and 25% for the Nonaggressive group, >96 months and 72% for the Resection/Ablation group, and 50 months and 50% for the TACE group. The survival for the Resection/Ablation and the TACE groups was significantly better (P < 0.05) when compared with the Nonaggressive group. Patients with more than 50% liver involvement had a poor outcome (P < 0.001). These data suggest that aggressive management of neuroendocrine hepatic metastases does improve survival, that chemoembolization increases the patient population eligible for this strategy, and that patients with more than 50% liver involvement may not benefit from an aggressive approach.

The influence of provocateurs’ emotion displays on the social information processing of children varying in social adjustment and age

This study examined the effect of provocateurs’ emotion displays on first through fourth graders’ social information processing (SIP). Rating and nomination sociometric techniques were used to identify rejected–aggressive, rejected–nonaggressive, average–nonaggressive, and popular–nonaggressive groups. Children viewed videotaped ambiguous provocation situations in which provocateurs’ emotion displays were varied systematically. After each vignette, children’s recall of story details, attribution of intent, and problem-solving responses were obtained. Half of the children were randomly assigned to a condition where they were asked directly about provocateurs’ emotions, and the remaining children were not asked about provocateurs’ feelings. Results revealed both developmental and social adjustment differences in SIP. In addition, provocateurs’ emotion displays and asking versus not asking about those displays influenced multiple aspects of SIP.

Controlling relationships in preschool children

In order to facilitate the comprehension of social structure in preschool children, our research has two foci: first, to define controlling behaviours (nonaggressive group organisation) and to determine their organisational principles, and second, to analyse the relation of the controlling behaviours with aggressive behaviours. Through direct observation, the behaviour of 90 preschoolers aged 4–5 years old during free playtime was registered. A correspondence analysis revealed that two organisational principles structure controlling relationships, one related to authority and another to acquiescence. The independence of these two dimensions suggests the existence of a social hierarchy in preschoolers’ playgroups based on controlling behaviour. No significant relation between authoritative and aggressive behaviours in 4-year-old children was detected, while 5-year-old children with high levels of authoritative behaviour were less aggressive than individuals with low levels. Our results point out that controlling activity is relevant in the organisation of preschool children’s social groups. Children’s goal development probably determines the change of the behavioural strategies that facilitate the evolution of social structure from aggressive to controlling hierarchies. We judge it necessary for research to focus on controlling interactions.

Aggression on a psychiatric acute ward: a three-year prospective study.

The objectives of this 3-yr. prospective study of aggression on a Norwegian psychiatric acute ward serving a population of 170,000 were to monitor the rate and characteristics of aggressive behaviour, to identify possible interactional and situational precipitants to aggression, and to explore possible differences between aggressive and nonaggressive patients in terms of diagnosis, sex, age, numbers of admissions, admission type, and length of stay. Aggressive incidents were recorded on the Report Form for Aggressive Episodes (REFA). Severity of injuries was scored according to Fottrell's severity scale. Of the total 934 patients admitted, 98 (10.5%) accounted for a total of 981 aggressive episodes. About 55% of the aggressive incidents were assaults that resulted in 85 minor and 21 severe physical injuries. There was no evidence that diagnosis might be used to predict aggression in the clinical setting. Mean rate of admission per patient and length of stay was significantly higher in the aggressive group than in the nonaggressive group. However, several patients in the aggressive group also had admissions without being aggressive. About 13% of the aggressive patients accounted for nearly 50% of the aggressive incidents. There was no significant sex difference by total rate of aggression, but female patients tended to have higher rates of assaults and contributed to significantly more injuries than male patients. Nearly 20% of the aggressive episodes occurred during the first 24 hours of a stay and 54% during the first week. Limit setting, problems in communication, and physical contact, separately or in combinations, preceded nearly 90% of the aggressive episodes.

Aggressive Children's Perceptions of Behaviorally Similar Peers: The Influence of One's Own Behavioral Characteristics on Perceptions of Deviant Peers

Students (grades 3, 7, and 10) classified as aggressive, withdrawn, or nondeviant responded to descriptions of four types of hypothetical male peers: aggressive (AG), withdrawn (WD), aggressive-withdrawn (AW), and neutral (NEU). Aggressive students were more likely to report that they would include the AG peer in social activities than did the withdrawn and nondeviant children. Similarly, the aggressive group had fewer negative affective responses to the AG peer stimuli than did the nonaggressive groups. Findings were consistent with other researchers' assertions that aggressive students evidence a self-serving bias in evaluations of their competence and a tendency to discount their role in aggressive exchanges. Within-subject differences revealed that, on some dimensions, aggressive children made fewer distinctions among the deviant hypothetical peers than did nondeviant and withdrawn children. Results are discussed in terms of how similarities between the perceiver and target can inform both research and clinical efforts to modify children's emotional and behavioral reactions to deviant peers.