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Purpose: Esophageal perforation (EP) can be a diagnostic challenge. Computed tomography (CT) and CT esophagography (CTE) are often used to rule out EP in the emergency setting with promising diagnostic performance, but the standard of care remains fluoroscopic esophagography (FE). We assess the diagnostic performance of CT and CTE when interpreted by expert and generalist radiologists and created an imaging workflow guide. Methods: Retrospective study of patients presenting with suspected EP. Two expert radiologists independently reviewed blinded CT/CTE studies, recorded CT findings, and assigned an esophageal injury grade. We also collected initial (general radiologist) CT findings and interpretation and FE diagnoses. We assessed inter-reader reliability and diagnostic performance. Results: EP was diagnosed in 46/139 (33%) encounters. The most common CT/CTE findings in EP were esophageal wall thickening (46/46, 100%), pneumomediastinum (42/46, 91%), and mediastinal stranding (39/46, 85%). CT and CTE sensitivity for detecting EP was 89% and 89% for expert radiologists, respectively, and 79% and 82% for general radiologists, compared with 46% for FE. Inter-reader agreement for detecting EP by CT and CTE was kappa 0.35 and 0.42 (both p <.001) between expert and generalist radiologists. We present radiographic images for key CT/CTE findings and a suggested workflow for the evaluation of possible EP. Conclusion: CT and CTE are more sensitive than FE for EP in the emergency setting. Due to the rarity of EP and current wide variability in imaging interpretation, an imaging workflow and injury grading system based on esophageal and mediastinal CT findings are offered to help guide management. [ABSTRACT FROM AUTHOR]

Peers are critical influencers of adolescent behavior, including defending against peer victimization. The current research explored peer influence processes associated with four different types of peer‐defending behaviors (comforting, reporting, solution‐focused, and aggressive defending behaviors) within early adolescent friendship networks. Links with peer victimization, friendship ties, and gender were also explored. Data were collected from 334 early adolescents ages 11–14 in Canada. Participants self‐reported on defending behaviors, victimization, and friendships over two time‐points, 8–10 weeks apart. Data were analyzed using Stochastic Actor‐Oriented Models (SAOMs). After controlling for friendship network structure and peer selection for defending behaviors, results indicated significant peer socialization effects for comforting, reporting, and solution‐focused defending. For solution‐focused defending only, the peer socialization effect was significantly stronger for girls than for boys. There were no significant selection effects across defending behaviors. In terms of social outcomes, youth with higher levels of reporting tended to have higher levels of peer victimization (and vice versa). Peer victimization was also positively associated with aggressive defending. Defending behaviors were generally unrelated to changes in friendship ties. Overall, these results highlight how friendships contribute to the development of peer‐defending behaviors and emphasize the need to examine defending as a multidimensional behavior. [ABSTRACT FROM AUTHOR]

Peers are present for most bullying episodes. Peers who witness bullying can play an important role in either stopping or perpetuating the behavior. Defending can greatly benefit victimized peers. Empathy is strongly associated with defending. Yet, less is known about defenders' neural response to witnessing social distress, and how this response may relate to the link between empathy and defending. Forty-six first-year undergraduate students (Mage = 17.7; 37 women), with varied history of peer defending, underwent fMRI scanning while witnessing a depiction of social exclusion. Functional connectivity analysis was performed across brain regions that are involved in cognitive empathy, empathetic distress, and compassion. History of defending was positively associated with functional connectivity (Exclusion > Inclusion) between the left orbitofrontal cortex (OFC) – medial prefrontal cortex (MPFC), and right OFC – left and right amygdalae. Defending was negatively associated with functional connectivity between the left OFC – anterior cingulate cortex. The relationship between history of defending and empathy (specifically, empathetic perspective taking) was moderated by functional connectivity of the right OFC – left amygdala. These findings suggest that coactivation of brain regions involved in compassionate emotion regulation and empathetic distress play a role in the relationship between empathy and peer defending. [ABSTRACT FROM AUTHOR]

Cystic fibrosis (CF) may predispose patients to urinary stone disease (USD), but reported prevalence of USD in patients with CF in previous small studies is variable. To date, analysis of risk factors for USD within the CF population has been limited. We studied 29,396 patients in the Cystic Fibrosis Foundation Patient Registry to calculate age and sex-stratified prevalence of USD. For adult patients, we examined age and multivariable-adjusted cross-sectional associations between demographic and clinical factors, CFTR mutation class, and prevalent USD. Prevalence of USD was 0.4% (95% CI 0.3–0.5%) under age 18 years, 3.1% (2.7–3.6%) at 18–24 years, 6.4% (5.8–7.1%) at 25–34 years, 7.5% (6.5–8.5%) at 35–44 years, and 6.7% (5.8–7.8%) at 45 years and older. Prevalence for women was higher than men at younger (< 45 years) but not older ages (P value for interaction < 0.0005). Multivariable odds of prevalent USD were significantly increased for severe CFTR mutations, OR 1.53 (1.14–2.06), diabetes, OR 1.24 (1.03–1.50), hypertension, OR 1.58 (1.29–1.93), and chronic macrolide therapy, OR 1.27 (1.07–1.52). BMI was not associated with USD. USD prevalence in CF is similar to that in the general population. With the exception of BMI, known risk factors for USD in the general population also appear to be important for patients with CF. We identified several novel associations in CF patients, including greater prevalence of USD in individuals with severe CFTR mutations and among young women. [ABSTRACT FROM AUTHOR]

Different patterns of sexting behaviors were examined to provide a more nuanced understanding of the context in which sexting occurs among adolescents. Participants were 1,000 Canadian adolescents (50.2% girls) between 12 and 18 years (M age = 15.21, SD = 2.00) who completed measures of sexting, cyber bullying and victimization, problematic social media use, self-regulation, and demographics. Contrary to our hypotheses, three latent profiles of sexting represented the frequency of sexting rather than whether the sexting was consensual versus non-consensual or with a partner versus non-partner. Participants in the moderate and high sexting profiles representing one fifth of youth, reported less self-regulation, experienced more cyber victimization, and engaged in more cyber bullying and problematic social media use than those in the no/low sexting profile. Our findings support the normalcy approach to education, which considers some sexting among healthy developmental behaviors. [ABSTRACT FROM AUTHOR]

This preliminary study explored a person-group dissimilarity hypothesis in the context of adolescent sexual harassment. Theory suggests that victimized youth are expected to experience worse outcomes if they perceive victimization to be a rare experience among their peers. This study comprised 435 middle school students who reported on their experiences of sexual harassment (victimization and witnessing), shame, and depressive symptoms. We tested a cross-sectional conditional indirect-effects model, with shame mediating the relationship between victimization and depressive symptoms (the indirect effect) and with witnessing as a moderator of the indirect effect. For all students, shame mediated the relationship between victimization and depressive symptoms. For female students, there was a buffering effect of witnessing, whereby the indirect effect was weaker at high levels of witnessing. These findings have potential implications for theory and intervention, suggesting the importance of examining young people's social contexts to better understand their responses to sexual harassment. [ABSTRACT FROM AUTHOR]

Defending represents any prosocial behavior taken to assist an individual being victimized. Like other forms of prosocial behavior, defending may be best conceptualized as a multidimensional set of behaviors, including both direct and indirect forms of defending. The objective of the current research was to design and validate the Defending Behaviors Scale (DBS), a multidimensional self-report scale of defending behaviors. Data were collected from 572 early adolescents in Grades 6 to 8. Participants completed the DBS as well as established measures of bullying, victimization, empathy, aggression, social self-efficacy, social support, and prosocial behavior. Data were analyzed using an exploratory structural equation modeling framework. A four-factor model provided the best fit to the data. Direct defending included aggressive and solution-focused behaviors, whereas indirect defending included comforting and reporting to authority. Girls were more likely to defend others by offering comfort and reporting to authority, whereas aggressive defending was more common among boys. Each subscale demonstrated good internal consistency (α's 0.80–0.92) and was uniquely associated with empathy, aggression, and other types of prosocial behavior. The DBS is a new, psychometrically-valid measure that will aid in the assessment of heterogenous defending behaviors. [ABSTRACT FROM AUTHOR]

Bullying and peer victimization are stressful experiences for youth, and are associated with increased risk for psychopathology. Physiological differences in the body's stress response system may help us to understand vulnerability for depressive symptoms among youth involved with bullying. The current study examined both sympathetic and parasympathetic activity using skin conductance (SCL) and respiratory sinus arrhythmia (RSA) at a neutral baseline and during Cyberball, a stressful social exclusion paradigm. Participants consisted of 175 youth in grades 6-11 (mean age 13.6 years, 51% girls). Multilevel modeling was used to examine changes in both positive and negative affect, and physiological stress reactivity over time. Logistic regression was used to examine the associations between bullying, victimization, and RSA on depressive symptoms. Peer victimization was negatively associated with resting RSA. Bullying others was negatively associated with SCL during Cyberball. Additionally, RSA reactivity during acute stress moderated the link between victimization and depressive symptoms. Victimization was more strongly associated with depressive symptoms when youth also demonstrated blunted RSA reactivity. These results suggest that both victimized youth and those who bully others have differences in their autonomic responses to acute stress. Individual differences in stress physiology may help us to understand vulnerability and resilience to depressive symptoms in the context of bullying and victimization. [ABSTRACT FROM AUTHOR]

Emotion socialization by close relationship partners plays a role in adolescent depression. In the current study, a microsocial approach was used to examine how adolescents' emotions are socialized by their mothers and close friends in real time, and how these interpersonal emotion dynamics are related to adolescent depressive symptoms. Participants were 83 adolescents aged 16 to 17 years who participated in conflict discussions with their mothers and self-nominated close friends. Adolescents' positive and negative emotions, and mothers' and peers' supportive regulation of adolescent emotions, were coded in real time. Two multilevel survival analyses in a 2-level Cox hazard regression framework predicted the hazard rate of (1) mothers' supportive regulation of adolescents' emotions, and (2) peers' supportive regulation of adolescents' emotions. The likelihood of maternal supportiveness, regardless of adolescent emotions, was lower for adolescents with higher depressive symptoms. In addition, peers were less likely to up-regulate adolescent positive emotions at higher levels of adolescent depressive symptoms. The results of the current study support interpersonal models of depression and demonstrate the importance of real-time interpersonal emotion processes in adolescent depressive symptoms. [ABSTRACT FROM AUTHOR]

Introduction: Previous research shows that adolescents who experience dating violence most often disclose their victimization to a peer or friend, more so than to other sources of support. However, surprisingly little research has explored how adolescents respond to peer disclosures of dating violence. Addressing this gap, the present study assessed variations in adolescents' perceptions of blame, interpretations of the incident as violence, and intentions to respond across physical, psychological, sexual, cyber‐psychological, and cyber‐sexual dating violence scenarios. Methods: As part of a national research project across Canada, 663 high school adolescents (432 girls, 65.2%) between the ages of 14‐17 were randomly assigned to complete a questionnaire which included one of five different hypothetical dating violence scenarios. Next, participants responded to questions about their perceptions of the incident, as well as victim and perpetrator blame and responsibility, and their intentions to respond. Results: Results indicated that the type of dating violence experienced and the age and gender of participants all played a role in perceptions of blame, understandings of violence, and intentions to respond. Conclusions: As one of the first studies to explore how adolescents perceived and responded to dating violence, considering both in‐person and cyber forms of dating violence, this study fills an important gap in the literature. Findings underscore the uniqueness of cyber forms of dating violence and how pre/intervention programs must address the specific contexts and issues unique to each type of dating violence. [ABSTRACT FROM AUTHOR]

Objective. Oral and injected steroids are used commonly in the treatment of cervical radicular pain despite a paucity of data demonstrating their efficacy. The purpose of this study is to assess whether the response to orally administered steroids among patients with acute cervical radicular pain who develop recurrent pain is associated with their subsequent response to cervical epidural steroid injections. Methods. Patients referred to our center were evaluated and then referred for cervical epidural steroid injections at the clinical discretion of the provider; those who met inclusion criteria were offered participation in the study. After the injectionwas administered, patients were contacted by telephone and asked to complete the Brief Pain Inventory Short Form at one week, one month, threemonths, and sixmonths postinjection. Results. Pain reduction after cervical steroid injection was not significantly different between 49 patients who reported pain reduction with a prior course of oral steroids and 22 patients who reported no pain reduction. Average pain scores decreased over six months (P< 0.001) among 72 patients treated with epidural steroid injection for cervical radicular pain. Of the 55 who provided baseline and six-month data, 14 (25.5%) reported complete relief at six months and 20 (36.4%) reported decreased pain. Conclusions. Patients can be reassured that they may experience pain reduction after a cervical epidural steroid injection even if oral steroid therapy was not effective. The majority of patients treated for cervical radicular pain with epidural steroid injection have reduced or absent pain for at least six months after treatment. [ABSTRACT FROM AUTHOR]

Current practices of identifying and treating small indolent thyroid cancers constitute an important but in some ways unusual form of overdiagnosis. Overdiagnosis refers to diagnoses that generally harm rather than benefit patients, primarily because the diagnosed condition is not a harmful form of disease. Patients who are overdiagnosed with thyroid cancer are harmed by the psycho-social impact of a cancer diagnosis, as well as treatment interventions such partial or total thyroidectomy, lifelong thyroid replacement hormone, monitoring, surgical complications and other side effects. These harms seem to outweigh any putative benefit of knowing about a cancer that would not have caused problems if left undiscovered. In addition to harms to patients, thyroid cancer overdiagnosis leads to significant opportunity costs at a societal level, due to costs of diagnosis and treatment. Unlike many other overdiagnosed cancers, accurate risk stratification is possible with thyroid cancer. At the individual patient level, use of this risk information might support informed choice and/or shared decision-making, as mandated by clinical ethics frameworks. And this approach might, to some extent, help to reduce rates of diagnosis and intervention. In practice, however, it is unlikely to stem the rising incidence and associated harms and costs of overdiagnosed thyroid cancer, especially in situations where health professionals have conflicts of interest. We argue in this article that thyroid cancer overdiagnosis may be usefully understood as a public health problem, and that some public health approaches will be readily justifiable and are more likely to be effective in minimising its harms. [ABSTRACT FROM AUTHOR]

Background: Youth involved with school bullying are vulnerable to many negative outcomes, including substance use. Research has yet to examine how this vulnerability operates in the context of other individual and neighbourhood differences. The current study aimed to fill this gap by using multilevel modeling to investigate both the individual and neighbourhood risk factors associated with frequent drunkenness and frequent cannabis use among adolescents.Methods: Data from the 2010 Canadian Health Behaviours in School-Aged Children (HBSC) survey were analyzed. Participants consisted of 8971 students from 173 neighbourhoods across Canada. Multilevel modeling was used to examine both individual (age, gender, bullying, victimization, peer deviancy, negative affect) and neighbourhood (socioeconomic status, crime, physical neighbourhood disorder, residential instability) risk factors. We tested whether the links between bullying involvement and frequent substance use were mediated by other risk factors.Results: Both individual and neighbourhood risk factors were associated with an increased likelihood of frequent substance use. Specifically, bullying served as a unique risk factor for frequent substance use over and above more traditional risk factors. A cross-level interaction was observed between residential instability and peer deviancy, such that the link between peer deviancy and frequent drunkenness was stronger in more residentially-unstable neighbourhoods. Peer deviancy partially mediated the link between bullying and both types of frequent substance use, whereas both peer deviancy and negative affect mediated the link between victimization and both types of frequent substance use.Conclusions: Youth who bully others are vulnerable to frequent substance use across peer and neighbourhood contexts. [ABSTRACT FROM AUTHOR]

• The frequency of clinical failure was similar in the continued IV and PO step-down groups (24.2% vs. 18.0%, P =0.23). • Hospital length of stay was longer in the IV group compared with the PO group (7 [5-13.5] vs. 4 [3–5] days, P <0.001). • The incidence of antibiotic adverse events was similar in the IV and PO groups (1.3% vs. 1.8%, P =0.74). The purpose of this study was to compare the clinical outcomes of adults with uncomplicated streptococcal bacteremia who received either oral (PO) step-down or continued intravenous (IV) therapy. This was a retrospective, single-center, cohort study, including adults admitted with Streptococcal bloodstream infection between January 1, 2013, and December 31, 2020. Only patients with uncomplicated Streptococcal bloodstream infections were included. Patients who transitioned to PO therapy within 5 days from bacteremia onset were compared to patients receiving continued IV therapy. The primary outcome was clinical failure, defined by either 90-day hospital readmission or mortality. Secondary outcomes included hospital length of stay (LOS) and antibiotic-related adverse events (AAEs). Of the 264 patients included, 42% were transitioned to PO therapy. Group B Streptococcus (22.7%) was the most common isolate. The most common sources of infection were skin and soft tissue (35%) and pulmonary (25%). Intensive care unit (ICU) stay was more common in the continued IV therapy group (22.2%) than in the PO step-down group (5.4%). The frequency of clinical failure was similar in the IV and PO groups (24.2% vs. 18.0%, P =0.23). The IV group had longer hospital LOS (median, [interquartile range (IQR)]) compared with the PO group (7 [5-13.5] vs. 4 [3–5] days, P <0.001). The incidence of AAEs was similar in the IV and PO groups (1.3% vs. 1.8%, P =0.74). Oral antibiotic step-down therapy may be appropriate for the treatment of uncomplicated Streptococcal bacteremia, with consideration of factors such as patient comorbidities, type of infection, source control and clinical progress. [ABSTRACT FROM AUTHOR]

For emerging adults, high-quality friendships can be an important source of companionship and support. The most commonly studied negative interaction between friends is conflict, yet work with youth suggests more serious victimization also occurs in friendship. In the current study, we developed and obtained preliminary psychometric evidence for the Friendship Victimization Scale, a measure that assesses physical, sexual, relational, and verbal forms of victimization in the friendships of emerging adults, as well as coercive and controlling behaviors. Emerging adults (N = 316, M age = 21.27 years, SD = 1.47; 60.4% women, 37.0% men; 59.2% White) completed the Friendship Victimization Scale along with measures to examine construct validity. The majority of the sample reported experiencing at least one act of victimization by a friend, and men reported more victimization than did women. Results supported a 2-factor structure, with relational and verbal victimization loading on one factor and physical and sexual victimization and controlling behaviors loading on the other. Cronbach's alphas exceeded.90 for the total score and both subscales. Greater friendship victimization was predicted by negative features in each of a best and a challenging friendship, even after accounting for negative features in a dating relationship, and was unrelated to positive features in any of these relationships. Overall, results indicate that victimization is common in emerging adults' friendships. The findings provide preliminary evidence for the utility of the Friendship Victimization Scale as a measure of this understudied source of risk in the interpersonal lives of emerging adults. [ABSTRACT FROM AUTHOR]

To compare the live birth rates (LBRs) in modified natural and programmed single blastocyst frozen embryo transfer (FET) cycles. Retrospective cohort study. University-affiliated fertility practice. Patients who underwent single blastocyst FETs between January 2014 and December 2019. A total of 15,034 FET cycles from 9,092 patients were reviewed; 1,186 modified natural and 5,496 programmed FET cycles from 4,532 patients met the inclusion criteria for analysis. No intervention. The primary outcome measure was the LBR. There was no difference in live birth after programmed cycles using intramuscular (IM) progesterone or a combination of vaginal progesterone and IM progesterone compared with that after modified natural cycles (adjusted relative risks, 0.94 [95% confidence interval {CI}, 0.85–1.04] and 0.91 [95% CI, 0.82–1.02], respectively). The relative risk of live birth decreased in programmed cycles that used exclusively vaginal progesterone compared with that in modified natural cycles (adjusted relative risk, 0.77 [95% CI, 0.69–0.86]). The LBR decreased in programmed cycles that used only vaginal progesterone. However, no difference in the LBRs existed between modified natural and programmed cycles if programmed cycles used either IM progesterone or a combination of IM and vaginal progesterone protocols. This study demonstrates that modified natural FET cycles and optimized programmed FET cycles have equivalent LBRs. [ABSTRACT FROM AUTHOR]

Several studies have now reported associations between gestational diabetes mellitus (GDM) and low free thyroxine (fT4) during the second and third trimesters, but not in the first trimester. The present study further examines relationships between low fT4, maternal weight, and GDM among women in the FaSTER (First and Second Trimester Evaluation of Risk) trial, in an effort to determine the extent to which thyroid hormones might contribute to causality. The FaSTER cohort includes 9351 singleton, euthyroid women; 272 of these women were subsequently classified as having GDM. Thyrotropin (TSH), fT4, and thyroid antibodies were measured at 11–14 weeks’ gestation (first trimester) and 15–18.9 weeks’ gestation (second trimester). An earlier report of this cohort documented an inverse relationship between fT4 in the second trimester and maternal weight. In the current analysis, women with GDM were significantly older (32 vs. 28 years) and weighed more (75 vs. 64.5 kg). Maternal weight and age (but not TSH) were significantly associated univariately with fT4 (dependent variable), in the order listed. Second trimester fT4 odds ratios (OR) for GDM were 2.06 [95% CI 1.37–3.09] (unadjusted); and 1.89 [95% CI 1.26–2.84] (adjusted). First trimester odds ratios were not significant: OR 1.45 [95%CI 0.97–2.16] (unadjusted) and 1.11 [95% CI 0.74–1.62] (adjusted). The second trimester fT4/GDM relationship thus appeared to strengthen as gestation progressed. In FaSTER, high maternal weight was associated with both low fT4 and a higher GDM rate in the second trimester. Peripheral deiodinase activity is known to increase with high caloric intake (represented by high weight). We speculate that weight-related low fT4 (the metabolically inactive prohormone) is a marker for deiodinase activity, serving as a substrate for conversion of fT4 to free triiodothyronine (fT3), the active hormone responsible for glucose-related metabolic activity. [ABSTRACT FROM AUTHOR]

A substantial minority of adolescents experience and use dating violence in their sexual and/or romantic relationships. Limited attention has been paid to exploring theory-driven questions about use and experience of adolescent dating violence (ADV), restricting knowledge about promising prevention targets for diverse groups of youth. To address this gap, this paper investigates whether factors tied to power imbalances (bullying, risk of social marginalization) are associated with patterns of ADV victimization and perpetration in a large sample of Canadian mid-adolescents. We used data from the 2017/2018 Health-Behavior in School-Aged Children (HBSC) study, a nationally representative sample of Canadian youth. Our study was comprised of adolescents who were in grades 9 or 10, and who had dated in the past 12 months (N = 3779). We assessed multiple forms of ADV and bullying victimization and perpetration. We also included six variables assessing adolescents' risk of social marginalization: gender, race/ethnicity, immigration status, family structure, food insecurity, and family affluence. We used latent class analysis to explore the ways adolescents experience and use different forms of ADV, and then examined whether factors tied to power imbalances (bullying, social marginalization) were associated with classes of ADV. Three ADV classes emerged in our sample: uninvolved (65.7%), psychological and cyber victimization only (28.9%), and mutual violence (5.4%). Bullying was most strongly associated with the mutual violence class, suggesting a transformation of power from peer to romantic contexts. Social marginalization variables were associated with ADV patterns in different ways, highlighting the need to use a critical and anti-oppressive lens in ADV research and prevention initiatives. [ABSTRACT FROM AUTHOR]

The present study explored the relationships between individual ethnicity and community ethnicity factors and the prevalence of racial bullying. It was hypothesized that individuals belonging to the majority ethnic group in a community were less racially victimized than in a community in which they were minority members. Data were collected from 20,021 students in Grades 6 to 10 as part of the 2009/2010 Health Behaviour in School-aged Children Survey, from Geographical Information Systems data, and from census data. Community diversity was associated with prevalence of racial victimization, although relationships differed by type of religious organization. Those of East/Southeast Asian, Caucasian, and South Asian ethnicity were more likely to be racially victimized in communities in which they were the minority ethnic group than when they were in the majority group. The importance of considering ethnicity characteristics that are related to racially focused bullying in the community context is discussed. [ABSTRACT FROM AUTHOR]

Background: This hypothesis generating study explores second trimester maternal body mass index (BMI) during pregnancy and offspring neurocognitive development. Methods: Mothers and offspring served as controls in two earlier studies: 101 children at age two years and 118 children at age eight years. Results: Frequency of maternal BMI ≥30 kg/m² increased from 10% in 1987-1990 to 30% in 2004-2006 (P, 0.001); the socioeconomic gradient became more pronounced. At age two, one or more BSID-III (Bayley Scales of Infant Development, 3rd Edition) scores ,85 were more frequent with higher maternal BMI (P = 0.029); regression analysis suggested an inverse relationship between language scores and BMI (P = 0.054). Among eight-year-olds, one or more WISC-III (Wechsler Intelligence Scale for Children, 3rd edition) scores ,85 increased with maternal BMI (P = 0.017); regression analysis showed an inverse relationship between performance subscale IQ score and BMI (P = 0.023). Conclusion: Second trimester maternal obesity may be an independent risk factor for some aspects of children's neurocognitive development. Further study is indicated. [ABSTRACT FROM AUTHOR]

Background: Among euthyroid pregnant women in a large clinical trial, free thyroxine (FT4) measurements below the 2.5th centile were associated with a 17 lb higher weight (2.9 kg/m2) than in the overall study population. We explore this relationship further. Methods: Among 9351 women with second trimester thyrotropin (TSH) measurements between 1st and 98th centiles, we examine: (i) the weight/FT4 relationship; (ii) percentages of women in three weight categories at each FT4 decile; (iii) FT4 concentrations in three weight categories at each TSH decile; and (iv) impact of adjusting FT4 for weight-in the reference group and in 190 additional women with elevated TSH measurements. Results: FT4 values decrease steadily as weight increases ( p<0.0001 by ANOVA) among women in the reference group (TSH 0.05-3.8 IU/L). TSH follows no consistent pattern with weight. When stratified into weight tertiles, 48% of women at the lowest FT4 decile are heavy; the percentage decreases steadily to 22% at the highest FT4 decile. Median FT4 is lowest in heaviest women regardless of the TSH level. In the reference group, weight adjustment reduces overall variance by 2.9%. Fewer FT4 measurements are at either extreme (below the 5th FT4 centile: 4.8% before adjustment, 4.7% after adjustment; above the 95th FT4 centile: 5.0% and 4.7%, respectively). Adjustment places more light weight women and fewer heavy women below the 5th FT4 centile; the converse above the 95th centile. Between TSH 3.8 and 5 IU/L, the FT4 percentage below the 5th FT4 centile is not elevated (3.8% before adjustment, 3.1% after adjustment). Percentage of FT4 values above the 95th centile, however, is lower (1.5% before adjustment, 0.8% after adjustment). Above TSH 5 IU/L, 25% of women have FT4 values below the 5th FT4 centile; weight adjustment raises this to 30%; no FT4 values remain above the 95th FT4 centile. Conclusions: During early pregnancy, TSH values are not associated with weight, unlike nonpregnant adults. Lower average FT4 values among heavy women at all TSH deciles partially explain interindividual differences in FT4 reference ranges. The continuous reciprocal relationship between weight and FT4 explains lower FT4 with higher weight. Weight adjustment refines FT4 interpretation. [ABSTRACT FROM AUTHOR]

Background: Postoperative quality of life (QoL) after surgery for Graves' disease is not well documented, and the effect of different surgical operations has not been compared. This study examines the impact on QoL of a shift in policy from operations intended to preserve thyroid function (PF) to those ablating thyroid function (AF). Methods: A cross-sectional assessment was performed on patients who underwent surgery for Graves' disease between 1986 and 2008 in a tertiary endocrine surgical unit. Patients completed the Short Form 36 (SF-36) questionnaire by post. SF-36 scores, including the physical and mental component summaries, were compared with the general population and by operative intent (AF vs. PF). Statistical analyses were performed using SPSS 16.0. Results: Of 150 patients, 3 had died of unrelated causes and 14 were not contactable. In the remaining 133 patients, the median age at time of assessment was 46 years (interquartile range 42-50) and 43 years (interquartile range 33-47) in the PF and AF groups, respectively. From these patients, 87 questionnaires (65.4% response rate) were completed with an item completion rate of 99.3%. The median follow-up was 18.4 years for PF and 7.9 years for AF surgery. Of 87 respondents, 38 (43.7%) underwent PF and 49 (56.3%) AF surgery. Study participants reported lower scores across all SF-36 subscales than British norms ( p<0.05). Comparisons on operative intent showed no significant difference in long-term QoL ( p>0.05). Conclusion: The shift to ablative surgery simplifies postoperative management with no adverse effect on QoL, justifying this practice from a patient perspective. [ABSTRACT FROM AUTHOR]

Background: Anti-extractable nuclear antigen antibodies (anti-ENA) have diagnostic significance in systemic rheumatic disease (SRD). Methods: Anti-ENA were tested in 1685/30,196 sera that were submitted sequentially for antinuclear antibody (ANA) testing. Frequency was stratified by ANA titer and pattern, by referral source, by submitted diagnosis and by patient age and sex. Results: Anti-ENA frequency increased with ANA titer (7.3% at <32%-43.3% at ≥1024). Anti-histone (11.6%) and anti-SSA/SSB (13.9%) were the most frequent finding with a homo\xadgeneous pattern; anti-SSA/SSB (39.7%) and anti-RNP/anti-Sm (37.7%) were the most frequent finding with a speckled pattern. Sera with speckled, multiple and homogenous ANA patterns accounted for 92.6% of positive anti-ENA findings. At ANA titer ≥256, 29.2% of these sera were tested for anti-ENA, of which 41.2% were positive; frequency was higher with an accompanying diagnosis of SRD (53.5% vs. 36.5%, p<0.004 by χ2-test) but not with referral by rheumatologists (43.5% vs. 35.9%) and did not differ by patient age or sex. Conclusions: Reflexive anti-ENA testing may be helpful among sera with ANA titer ≥256 and homogeneous, speckled or multiple patterns, irrespective of referral source or accompanying diagnosis. Further work is needed to evaluate the clinical impact of this protocol. [ABSTRACT FROM AUTHOR]

The Promoting Relationships and Eliminating Violence Network (PREVNet) involves Canadian researchers and national organizations working to promote healthy relationships and prevent bullying. In this paper, we provide the rationale for establishing PREVNet, a description of the work of the network, and an assessment of the success of PREVNet. PREVNet’s strategic plan focuses on enhancing the practice of those who work with children and youth through knowledge mobilization under four strategy pillars: education and training, assessment and evaluation, prevention and intervention, and policy and advocacy. For this paper, we focus on proximal indicators of PREVNet’s success: growth of the network, participation in network activities, and development of knowledge mobilization resources. We illustrate that building partnerships with national organizations has been highly effective in the generation and dissemination of knowledge relating to children’s healthy development and healthy relationships. [ABSTRACT FROM PUBLISHER]

Background: We examined the relationship between antinuclear antibody (ANA) data and the presence of anti-double stranded DNA antibodies (anti-dsDNA). Methods: De-identified demographic, ANA and anti-dsDNA data were available for 30,196 individuals aged ≥20 years, whose sera were submitted sequentially to our laboratory. When multiple sera were received for the same subject, data from the earliest sample were used. Anti-dsDNA frequency was stratified by ANA titer and pattern, sample referral source, and by the patient's age, gender, and diagnosis. Results: For sera with ANA titer ≥256 and an accompanying diagnosis of systemic lupus erythematosus, anti-dsDNA frequency was 53.7%, 35.3%, and 37.5% for homogeneous, speckled, or multiple ANA patterns, respectively. Among remaining sera with ANA titer ≥256, anti-dsDNA frequency was highest for the homogeneous pattern (15.9%). Anti-dsDNA frequency was three-fold higher among sera submitted by rheumatologists compared with other providers. However, its relative distribution by ANA pattern and titer was similar between these groups. Patient age and gender had no significant effect on anti-dsDNA frequency after ANA data were taken into account. Conclusions: ANA pattern and titer, together with the diagnosis submitted with the serum sample, can be used to guide decisions for reflexive anti-dsDNA testing in a clinical laboratory setting. [ABSTRACT FROM AUTHOR]

The intentional introduction into the environment or market of genetically modified organisms (GMOs) is nearly always governed by a framework of science-based risk assessment and risk management measures. This is usually implemented through the integration of hazard identification and characterisation of all of the elements of risk associated with a new GM crop or derived product. Typical categories of hazards arising from the introduction of transgenic crops include: possible unintended negative health effects in a susceptible subgroup of the consumer (target) population; the evolution of resistance in the targeted pest/pathogen populations when the transgene confers resistance to a pest or pathogen; non-target hazards associated directly or indirectly with the transgenic plant or transgene product outside the plant; and those associated with the integration and subsequent expression of the transgene in a different organism or species following gene flow. The consequences of likely exposure to these and other hazards are considered in this introduction to the main issues raised when evaluating the possible risks arising from the importation or cultivation of genetically modified crops. [ABSTRACT FROM AUTHOR]

Objective: To examine the developmental eating trajectories of adolescents and identify psychological correlates and risk factors associated with those trajectories. Method: Seven hundred thirty-nine adolescents completed self-reported measures of eating problems, internalizing and externalizing behaviors, alcohol and drug use, peer victimization, and depression. Results: Five eating trajectories were obtained. The proportions of males and females were the same in the increasing eating problems trajectory. For both genders, internalizing and externalizing problems were identified as associated risk factors of an eating pathology and reporting at least some eating problems was associated with an increased likelihood of psychological problems. Other risk factors found only in boys were frequency of drug use, victimization, and depressive symptoms. Conclusion: Externalizing problems in girls and internalizing behaviors in boys with disordered eating should not be overlooked. Atypical eating behaviors in boys are of particular concern since it increases their risk of cooccurring psychopathology. © 2008 by Wiley Periodicals, Inc. Int J Eat Disord 2008 [ABSTRACT FROM AUTHOR]

The present study examined physical dating aggression in different adolescent relationships and assessed linear, threshold, and moderator risk models for recurrent aggressive relationships. The 621 participants (59% girls, 41% boys) were drawn from a 1-year longitudinal survey of Canadian high school youths ranging from Grade 9 through Grade 12. Approximately 13% of participants reported recurrent dating aggression across 2 different relationships. Using peer and dyadic risk factors from Time 1 of the study, the authors confirmed a linear risk model, such that adolescents in 2 different violent relationships had significantly more contextual risk factors than did adolescents in 1 or no violent relationship. Further, structural equation modeling assessing moderation of contextual risk factors indicated that, for adolescents with high acceptance of dating aggression, peer aggression and delinquency significantly predicted recurrent aggression in a new relationship. In comparison, for adolescents with low acceptance of dating aggression, negative relationship characteristics significantly predicted recurrent aggression. Acceptance did not moderate concurrent associations between risk factors and aggression in 1 relationship. Results support a developmental psychopathological approach to the understanding of recurrent aggression and its associated risk factors. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine whether using the Internet for different activities affects the quality of close adolescent relationships (i.e., best friendships and romantic relationships). In a one-year longitudinal study of 884 adolescents (Mean age = 15, 46% male), we examined whether visiting chat rooms, using ICQ, using the Internet for general entertainment, or participating in online gaming predicted changes in the quality of best friendships and romantic relationships. Multiple regression analyses indicated that Internet activity choice influenced later relationship quality in both best friendships and romantic relationships. Using instant messaging (ICQ) was positively associated with most aspects of romantic relationship and best friendship quality. In contrast, visiting chat rooms was negatively related to best friendship quality. Using the Internet to play games and for general entertainment predicted decreases in relationship quality with best friends and with romantic partners. These findings reflect the important and complex functions of online socialization for the development and maintenance of relationships in adolescence. [ABSTRACT FROM AUTHOR]

Children who are bullied are often told to 'solve the problems themselves'; however, when bullying is repeated over time, it becomes increasingly difficult for victimized children to stop the torment because of their relative lack of power. We examine the ways in which children respond to bullying and their evaluations of the effectiveness of various strategies in reducing their bullying problems. One thousand eight hundred and fifty-two Canadian children and youth, ranging in age from 4- to 19-years-old (mean 12.6, SD 2.4) responded to a web-based questionnaire. Few respondents indicated that they were motivated by public education campaigns or information about bullying. Participants indicated they were motivated to do something to stop bullying by their own need to exert control and be assertive and by their emotional reactions to bullying. A significant group of youth responded that they did nothing to stop bullying. Finally, the longer the bullying had been ongoing, the less effective students perceived their own strategies. The results highlight the importance of adults supporting students. Similarly, it is important to provide children and youth with strategies that are effective, as they are most likely to implement strategies that are only going to increase the victimization over time. [ABSTRACT FROM AUTHOR]

Background: There are currently no guidelines concerning additional laboratory testing for specific autoantibodies among anti-nuclear antibody-negative sera with an anti-cytoplasmic staining pattern identified by indirect immunofluorescence assay. Moreover, few data are available that address this laboratory situation. Methods: We performed specific autoantibody assays in 200 sera with an anti-nuclear antibody titer ≤1:32 and a cytoplasmic titer (undefined staining pattern) of ≥1:64, identified sequentially in the course of routine anti-nuclear antibody testing. Results: A total of 85 sera (42.5%) were positive in one (n=57) or more (n=28) of the specific autoantibody tests performed. Autoantibodies identified were antimitochondrial (15%), antimicrosomal (13%), anti-neutrophil cytoplasmic (10%), anti-smooth muscle (6%), anti-parietal cell (4%), and extractable nuclear antigen (8.5%, including histones, SSA, SSB, Sm, Jo-1 or Scl-70). A positive result in one or more of these assays was more frequent at anti-cytoplasmic titers ≥1:1024 (77.8%) than at titers of 1:64–1:128 (7%) (χ2=25.3, p<0.001). Conclusions: The present data demonstrate that undefined anti-cytoplasmic staining in anti-nuclear antibody-negative sera is associated with, although not necessarily caused by, a high frequency and wide range of specific autoantibodies. Further work is needed before specific recommendations can be made concerning follow-up in subjects with this laboratory finding. Clin Chem Lab Med 2006;44:1283–6. [ABSTRACT FROM AUTHOR]

In this paper, we examined the forms and relationship contexts of bullying in adolescence. Using cross-sectional data, we assessed grade and sex differences in self-reports of bullying and sexually harassing peers, as well as reports of dating aggression from1896 students from early to late adolescence. Reports of bullying others were highest around the school transition, with lowest levels at the end of high school. Boys reported more bullying and sexual harassment than girls. Sexual harassment of same- and opposite-sex peers increased over the early adolescent years and leveled off in later high-school years. There were no sex differences in the prevalence of indirect or physical aggression with a dating partner. Adolescents who bullied were at increased risk for the other forms of relationship aggression. These data highlight bullying as a relationship problem and point to the need for prevention programs to curtail the use of power and aggression in adolescent relationships. Aggr. Behav. 32:376–384, 2006. © 2006 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

This study examined dating-stage and developmental-contextual models of romantic relationships during early adolescence. Same-gender friendships, affiliation with mixed-gender groups, dating, and romantic relationships were investigated in a sample of 1,284 young adolescents of diverse ethnocultural backgrounds. Data were collected cross­sectionally in Grades 5 through 8, as well as longitudinally in the fall and spring of an academic year. Consistent with a stage model, affiliation with mixed-gender groups and dating were qualitatively distinct activities that were sequentially organized and facilitated the progression from same-gender friendships to dyadic romantic relationships. The results also provide insights on how the developmental context may alter stage pathways: Dating activities were incorporated with mixed-gender affiliations, group-based romantic stages showed more stability than other stages, and the ethnocultural context influenced romantic timing. Finally, results indicated that participation in romantic activities heightened adolescents' future interest in having a romantic relationship. [ABSTRACT FROM AUTHOR]

Objective. The prevalence of overweight and obesity in children is rising. Childhood obesity is associated with many negative social and psychological ramifications such as peer aggression. However, the re-lationship between overweight and obesity status with different forms of bullying behaviors remains unclear. The purpose of this article is to examine these relation-ships. Methods. We examined associations between bully-ing behaviors (physical, verbal, relational, and sexual harassment) with overweight and obesity status in a rep-resentative sample of 5749 boys and girls (11--16 years old). The results were based on the Canadian records from the 2001/2002 World Health Organization Health Behaviour in School-Aged Children Survey. Body mass index (BMI) and bullying behaviors were determined from self-reports. Results. With the exception of 15- to 16-year-old boys, relationships were observed between BMI category and peer victimization, such that overweight and obese youth were at greater relative odds of being victims of aggres-sion than normal-weight youth. Strong and significant associations were seen for relational (eg, withdrawing friendship or spreading rumors or lies) and overt (eg, name-calling or teasing or hitting, kicking, or pushing) victimization but not for sexual harassment. Independent of gender, there were no associations between BMI cat-egory and bully-perpetrating in 11- to 14-year-olds. How-ever, there were relationships between BMI category and bully-perpetrating in 15- to 16-year-old boys and girls such that the overweight and obese 15- to 16-year-olds were more likely to perpetrate bullying than their nor-mal- weight classmates. Associations were seen for rela-tional (boys only) and overt (both genders) forms of bully-perpetrating but not for sexual harassment. Conclusions. Overweight and obese school-aged chil-dren are more likely to be the victims and perpetrators of bullying behaviors than their... [ABSTRACT FROM AUTHOR]

Bullying is a relationship problem in which power and aggression are used to cause distress to a vulnerable person. To assess and address bullying and victimization, we need to understand the nature of the problem, how the problem changes with age and differs for boys and girls, the relevant risk factors (those individual or environmental indicators that may lead to bullying and victimization), and the protective factors that buffer the impact of risk. For children involved in bullying, we need to assess its extent and the associated social, emotional, psychological, educational, and physical problems. Bullying is a systemic problem; therefore, assessments of bullying need to extend beyond the individual child to encompass the family, peer group, school, and community. We recommend that assessments at each of these levels reflect the scientific research on bullying and victimization. With attention to the problems associated with bullying, we can work collectively to make schools and communities safer for children and youth. [ABSTRACT FROM AUTHOR]

This study examined the stability of belonging to a gang in early adolescence, the behaviour profiles, family characteristics, and friendships of nongang and gang members. The subjects in the present study were originally part of a larger sample of boys. One hundred and forty-two boys who had a complete data set at ages 11, 12, 13, and 14 were selected for the present study. Loglinear analyses indicated that gang membership was stable from ages 13 to 14, but not at earlier ages. Boys were divided into three groups: stable gang members (children who belonged to a gang at ages 13 and 14); unstable gang members (children who belonged to a gang at either age 13 or 14) and nongang members. Repeated analyses of variance indicated that stable gang members had significantly higher scores than nongang members on teacher ratings of fighting behaviour, hyperactivity, inattention and oppositional behaviour, and self-reported delinquent activities (drug and alcohol use, stealing and vandalism). Peers rated gang members as more aggressive than nongang members. The results are discussed from a developmental perspective. [ABSTRACT FROM AUTHOR]

Research suggests that victims of bullying may lack skills in emotional regulation, a process which facilitates coping with provocative situations to lessen the stress of negative emotions (Cicchetti, Ackerman, & Izard, 1995). The present study examined the emotional regulation and display patterns of victims during classroom bullying episodes. Children in grades one through six were observed during free play in the winter and spring of three consecutive school years. Results of the study indicated that the coping styles observed in victims of bullying can be grouped into two distinct clusters: 1) problem-solving strategies that are associated with the de-escalation and resolution of bullying episodes; and 2) aggressive strategies that tend to perpetuate and escalate the bullying interaction. Parallels were found between victims' and bullies' emotional displays. Results are discussed in the context of how maladaptive emotional regulation processes may act as risk factors for chronic victimization. [ABSTRACT FROM AUTHOR]

The present study employed naturalistic observations to compare bullying and victimization in the playground and in the classroom. The results indicated that there were more opportunities to observe aggression and receive and initiate aggression in the playground than in the classroom. The frequency of bullying was higher in the playground (4.5 episodes per hour) than in the classroom (2.4 episodes per hour). The nature of bullying reflected the constraints of the context (i.e. direct bullying was more prevalent in the playground and indirect bullying was more prevalent in the classroom). Being at the receiving end of aggression was more likely to occur in the playground as compared to the classroom. Nonaggressive children were more likely to bully in the playground, whereas aggressive children were more likely to bully in the classroom. There was no difference across context in the proportion of episodes of reinforcement with peers present or in the rate of peer and teacher intervention. The results highlight the necessity of a systemic intervention programme that addresses not only the individual characteristics of bullies and victims, but also the roles of the peer group, teachers and the school. [ABSTRACT FROM AUTHOR]

In the present study, the effects of both contextual and individual factors on attitudes toward bullying among prospective teachers were examined. Contextual factors included type of aggression and the condition of having witnessed bullying. Individual factors included sex, age, empathy, sex role orientation and belief in a just world. A MANCOVA revealed no sex differences, but there was a significant main effect of the contextual factors on (a) the extent to which acts were labelled as bullying, (b) the perceived seriousness of bullying and (c) the likelihood of intervention. Physical types of aggression were labelled more often as bullying, were viewed more seriously and were more likely to warrant intervention than verbal aggression. Multiple regression analysis revealed that type of aggression, witnessing the interaction, empathy, masculinity and femininity predicted intolerant attitudes toward bullying. The results are discussed with reference to intervening in the problem of bullying. [ABSTRACT FROM AUTHOR]

Background: Transversus abdominis plane blocks are an established method of postoperative analgesia for abdominopelvic surgeries. Liposomal bupivacaine is an extended‐release formulation of bupivacaine providing up to 72 h of analgesia. This study aims to determine if transversus abdominis plane blocks performed with liposomal bupivacaine are associated with reduced opioid consumption and level of pain intensity compared to conventional bupivacaine in patients undergoing lower abdominal surgery. Methods: This retrospective cohort study was conducted at a single institution between December 2020 and December 2021. After institutional review board approval, we identified patients who underwent lower abdominopelvic surgery with transversus abdominis plane blocks done with liposomal or conventional bupivacaine and collected demographic, clinical, and procedural information for analysis. We compared total opioid consumption over 72‐h postoperatively in milligram morphine equivalents (MME), frequency of opioid utilization, and average level of pain intensity between groups. These outcomes were also evaluated after adjusting for covariates. Data were presented as mean ± SD, median [IQR] or frequency (%), as appropriate; p < 0.05 was accepted as significant. Results: A total of 178 patients met inclusion criteria, with 79 patients receiving an admixture of liposomal bupivacaine and conventional bupivacaine and 99 patients receiving conventional bupivacaine. The liposomal bupivacaine group had a median opioid consumption 72‐h postoperatively of 47.5 [18–91.8] MME compared to 88 [43.8–160] MME in the conventional bupivacaine group, p = 0.045. Differences in opioid consumption between the groups did not reach statistical significance after adjustment for demographic and clinical characteristics, p = 0.11. There was no significant difference in frequency of opioid use or average pain intensity. Conclusion: Transversus abdominis plane blocks using an admixture of liposomal bupivacaine conventional bupivacaine are not associated with decreased opioid consumption or reduced pain up to 72 h following elective abdominopelvic surgery. [ABSTRACT FROM AUTHOR]

Peers have both positive and negative influences on children; therefore, considerable attention has focused on assessing peer relationships and friendships through childhood and adolescence. The present article provides an overview of the main methods of assessing peer relationships. The adaptive nature of children's peer relations has been assessed through four main methodologies: (1) asking the children themselves about elements of peer relations and friendships; (2) asking children about their perceptions of others within the peer group; (3) asking adults (i.e. parents and teachers) about the peer relations skills of children in their care; and (4) directly observing children during interactions with peers. Each of these approaches is described, with attention to relative strengths and weaknesses and their suitability for assessing peer relations in early childhood, middle childhood, and adolescence. [ABSTRACT FROM AUTHOR]

Presents information on a study which explored adolescents conceptions of cross-sex friendships and romantic relationships. Characterization of romantic relationships and cross-sex friendships; Association of age and experience with changes in the use of descriptors; Result of the study.

Examines stable social maladjustment at ages 10, 11 and 12 from teacher behavioral ratings in kindergarten and a measure of family demographics. Collection of sociodemographic information from parents; Documentation of school achievements; Predictors for negative outcomes.

Abstract. In this meta-analysis it was demonstrated that, when compared with nonsmokers of similar age, smokers in the 8- to 19-year-old age group have significantly higher serum levels of triglyceride (+11.8%), very low-density lipoprotein (VLDL)-cholesterol (+12.4%) and low-density lipoprotein (LDL)-cholesterol (+4.1%) and significantly lower serum levels of high-density lipoprotein (HDL)-cholesterol (-8.5%) and total cholesterol (-3.7%). All of these smoking-associated changes are in the same direction as those found in adults, with the exception of total cholesterol levels, which are significantly increased in adult smokers. The extent to which mean triglyceride, LDL-cholesterol, and HDL-cholesterol levels are shifted is significantly greater in the 8- to 19-year-old smokers than in adult smokers. The changes in mean total cholesterol levels among smokers in both age groups represent only the net shifts in the lipoprotein fractions and are therefore likely to be a less sensitive indicator of the possible lipid-related excess coronary artery disease risk in smokers. [ABSTRACT FROM AUTHOR]

Presents a study which observed aggressive and nonaggressive behavior in children in elementary school. Difference in behavior exhibited by aggressive and nonaggressive children; What these early patterns of behavior are indicative of in adulthood; Implications of the behavior observed for the understanding of peer interactions.

Examines the association between cigarette smoking among adults in the United States. Discussions on the level of serum lipid and lipoprotein concentrations; Significance of dose response effects on heavy smokers; Risk of coronary artery disease for smokers with high cholesterol concentration.

Describes a methodology suited to study peer interactions, particularly those of aggressive children. Laboratory observational studies; Naturalistic observations; Remote audiovisual observations.