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Surveys of larval diversity consistently increase biodiversity estimates when applied to poorly documented groups of marine invertebrates such as phoronids and hemichordates. However, it remains to be seen how helpful this approach is for detecting unsampled species in well‐studied groups. Echinoids represent a large, robust, well‐studied macrofauna, with low diversity and low incidence of cryptic species, making them an ideal test case for the efficacy of larval barcoding to discover diversity in such groups. We developed a reference dataset of DNA barcodes for the shallow‐water adult echinoids from both coasts of Panama and compared them to DNA sequences obtained from larvae collected primarily on the Caribbean coast of Panama. We sequenced mitochondrial cytochrome c oxidase subunit I (COI) for 43 species of adult sea urchins to expand the number and coverage of sequences available in GenBank. Sequences were successfully obtained for COI and 16S ribosomal DNA from 272 larvae and assigned to 17 operational taxonomic units (OTUs): 4 from the Pacific coast of Panama, where larvae were not sampled as intensively, and 13 from the Caribbean coast. Of these 17 OTUs, 13 were identified from comparisons with our adult sequences and belonged to species well documented in these regions. Another larva was identified from comparisons with unpublished sequences in the Barcode of Life Database (BOLD) as belonging to Pseudoboletia, a genus scarcely known in the Caribbean and previously unreported in Panama. Three OTUs remained unidentified. Based on larval morphology, at least two of these OTUs appeared to be spatangoids, which are difficult to collect and whose presence often goes undetected in standard surveys of benthic diversity. Despite its ability to capture unanticipated diversity, larval sampling failed to collect some species that are locally common along the Caribbean coast of Panama, such as Leodia sexiesperforata, Diadema antillarum, and Clypeaster rosaceus. [ABSTRACT FROM AUTHOR]

Background: A better understanding of factors contributing to the observed variability in estimates of test–retest reliability in published studies on standardized diagnostic interviews (SDI) is needed. The objectives of this systematic review and meta‐analysis were to estimate the pooled test–retest reliability for parent and youth assessments of seven common disorders, and to examine sources of between‐study heterogeneity in reliability. Methods: Following a systematic review of the literature, multilevel random effects meta‐analyses were used to analyse 202 reliability estimates (Cohen's kappa = ҡ) from 31 eligible studies and 5,369 assessments of 3,344 children and youth. Results: Pooled reliability was moderate at ҡ = .58 (CI 95% 0.53–0.63) and between‐study heterogeneity was substantial (Q = 2,063 (df = 201), p < .001 and I2 = 79%). In subgroup analysis, reliability varied across informants for specific types of psychiatric disorder (ҡ = .53–.69 for parent vs. ҡ = .39–.68 for youth) with estimates significantly higher for parents on attention deficit hyperactivity disorder, oppositional defiant disorder and the broad groupings of externalizing and any disorder. Reliability was also significantly higher in studies with indicators of poor or fair study methodology quality (sample size <50, retest interval <7 days). Conclusions: Our findings raise important questions about the meaningfulness of published evidence on the test–retest reliability of SDIs and the usefulness of these tools in both clinical and research contexts. Potential remedies include the introduction of standardized study and reporting requirements for reliability studies, and exploration of other approaches to assessing and classifying child and adolescent psychiatric disorder. [ABSTRACT FROM AUTHOR]

Exposure to early adversity is known to have deleterious effects on brain-behaviour relations across the lifespan and across a range of domains. Here, we tested a cumulative risk hypothesis of adult social functioning and health outcomes in the fourth decade of life, using the oldest known longitudinally followed cohort of survivors of extremely low birthweight ( ELBW; <1,000 g). We investigated the additional impact of peer victimization in youth on social outcomes at age 29-36 years in ELBW survivors and matched normal birthweight ( NBW; >2,500 g) participants. In the combined sample, peer victimization was associated with lower likelihood of having children and household income, poorer family functioning and self-esteem, more loneliness and chronic health conditions, less social support, and increased likelihood for contact with police. Moderation analyses indicated that among ELBW survivors, compared to their NBW counterparts, victimization was more strongly associated with being convicted of a crime and with having chronic health conditions. These findings highlight the negative long-term impact of peer victimization on all children and that some outcomes may be differentially affected by prenatal and early post-natal environments. [ABSTRACT FROM AUTHOR]

Objective To describe the developmental trajectories of quality of life (QoL) in a large cohort of children with epilepsy, and to assess the relative contribution of clinical, psychosocial, and sociodemographic variables on QoL trajectories. Methods Five assessments during a 28-month prospective cohort study were used to model trajectories of QoL. Participants were recruited with their parents from six Canadian tertiary centers. A convenience sample of 506 children aged 8-14 years with epilepsy and without intellectual disability or autism spectrum disorder were enrolled. A total of 894 children were eligible and 330 refused participation. Participating children were, on average, 11.4 years of age, and 49% were female. Nearly one third (32%) had partial seizures. At baseline, 479 and 503 child- and parent-reported questionnaires were completed. In total, 354 children (74%) and 366 parents (73%) completed the 28-month follow-up. QoL was measured using the child- and parent-reported version of the Childhood Epilepsy QoL scale (CHEQOL-25). Results Child-reported QoL was fitted best by a six-class model and parent-reported QoL by a five-class model. In both models, trajectories remained either stable or improved over 28 months. Of these children, 62% rated their QoL as high or moderately high, defined as at least one standard deviation above the average CHEQOL-25 score. Greater family, classmate, and peer social support, fewer symptoms of child and parent depression, and higher receptive vocabulary were identified as the most robust predictors of better QoL (all p < 0.001). Significance Most children with epilepsy and their parents reported relatively good QoL in this first joint self- and proxy-reported trajectory study. Findings confirm the heterogeneous QoL outcomes for children with epilepsy and the primary importance of psychosocial factors rather than seizure and AED-specific factors in influencing QoL. These predictors that are potentially amenable to change should now be the focus of specific intervention studies. [ABSTRACT FROM AUTHOR]

The prevalence of suicidal ideation/behavior in 1983 or 1987 and its association with future mental health in 2001 were evaluated in a provincially representative sample of Canadian adolescents ( n = 1,248) aged 12 to 16 years. Approximately 13.3% (95% CI = 11.5-15.3) of adolescents self-reported suicidal ideation/behavior. Adolescent agreement with parent (κ = .07) and teacher (κ = .05) reports at baseline was low because adults identified so few subjects. In adulthood, the associations between adolescent self-reports of suicidal behavior/ideation and major depression and other mental health indicators were explained by respondent sex and adolescent emotional problems reported in 1983/1987. Adolescents with suicidal behavior/ideation often are not recognized by their parents and teachers and may be at risk for persistent psychiatric problems attributable to coexisting mental health problems early-on. [ABSTRACT FROM AUTHOR]

Background: Autism spectrum disorder (ASD) is characterized by notable phenotypic heterogeneity, which is often viewed as an obstacle to the study of its etiology, diagnosis, treatment, and prognosis. On the basis of empirical evidence, instead of three binary categories, the upcoming edition of the DSM 5 will use two dimensions - social communication deficits (SCD) and fixated interests and repetitive behaviors (FIRB) - for the ASD diagnostic criteria. Building on this proposed DSM 5 model, it would be useful to consider whether empirical data on the SCD and FIRB dimensions can be used within the novel methodological framework of Factor Mixture Modeling (FMM) to stratify children with ASD into more homogeneous subgroups. Methods: The study sample consisted of 391 newly diagnosed children (mean age 38.3 months; 330 males) with ASD. To derive subgroups, data from the Autism Diagnostic Interview-Revised indexing SCD and FIRB were used in FMM; FMM allows the examination of continuous dimensions and latent classes (i.e., categories) using both factor analysis (FA) and latent class analysis (LCA) as part of a single analytic framework. Results: Competing LCA, FA, and FMM models were fit to the data. On the basis of a set of goodness-of-fit criteria, a 'two-factor/three-class' factor mixture model provided the overall best fit to the data. This model describes ASD using three subgroups/classes (Class 1: 34%, Class 2: 10%, Class 3: 56% of the sample) based on differential severity gradients on the SCD and FIRB symptom dimensions. In addition to having different symptom severity levels, children from these subgroups were diagnosed at different ages and were functioning at different adaptive, language, and cognitive levels. Conclusions: Study findings suggest that the two symptom dimensions of SCD and FIRB proposed for the DSM 5 can be used in FMM to stratify children with ASD empirically into three relatively homogeneous subgroups. [ABSTRACT FROM AUTHOR]

Objective: The objective of this study was to chart the developmental trajectories of high-functioning children with autism spectrum disorders (ASD) from early childhood to adolescence using the presence and absence of structural language impairment (StrLI) as a way of differentiating autism from Asperger syndrome (AS). Method: Sixty-four high-functioning children with ASD were ascertained at 4–6 years of age from several different regional diagnostic and treatment centers. At 6–8 years of age, the ADI-R and the Test of Oral Language Development were used to define an autism group (those with StrLI at 6–8 years of age) and an AS group (those without StrLI). Growth curve analysis was then used to chart the developmental trajectories of these children on measures of autistic symptoms, and adaptive skills in communication, daily living and socialization. Results: Differentiating the ASD group in terms of the presence/absence of StrLI provided a better explanation of the variation in growth curves than not differentiating high-functioning ASD children. The two groups had similar developmental trajectories but the group without StrLI (the AS group) was functioning better and had fewer autistic symptoms than the group with StrLI (the autism group) on all measures across time. The differences in outcome could not be explained by non-verbal IQ or change in early language skills. Conclusion: Distinguishing between autism and Asperger syndrome based on the presence or absence of StrLI appears to be a clinically useful way of classifying ASD sub-types. [ABSTRACT FROM AUTHOR]

We examined receptive language and academic abilities in children with selective mutism (SM; n = 30; M age = 8.8 years), anxiety disorders (n = 46; M age = 9.3 years), and community controls (n = 27; M age = 7.8 years). Receptive language and academic abilities were assessed using standardized tests completed in the laboratory. We found a significant group by sex interaction for receptive vocabulary scores such that, within females, the SM and mixed anxiety groups had significantly lower receptive vocabulary scores than community controls. We also found that children with SM and children with anxiety disorders had significantly lower mathematics scores than community controls. Despite these differences in mathematics and receptive vocabulary performance, children with SM and children with anxiety disorders still performed at age-level norms, while more children in the community control group performed above age-level norms. Findings suggest that despite their speaking inhibition in the school setting, children with SM are still able to attain the receptive vocabulary and academic abilities that are expected at their age levels. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Post-traumatic stress disorder (PTSD) has become a global health issue, with prevalence rates ranging from 1.3% to 37.4%. As there is little current data on PTSD in Canada, an epidemiological study was conducted examining PTSD and related comorbid conditions. Modified versions of the Composite International Diagnostic Interview (CIDI) PTSD module, the depression, alcohol and substance abuse sections of the Mini International Neuropsychiatric Interview (MINI), as well as portions of the Childhood Trauma Questionnaire (CTQ) were combined, and administered via telephone interview in English or French. Random digit dialing was used to obtain a nationally representative sample of 2991, aged 18 years and above from across Canada. The prevalence rate of lifetime PTSD in Canada was estimated to be 9.2%, with a rate of current (1-month) PTSD of 2.4%. Traumatic exposure to at least one event sufficient to cause PTSD was reported by 76.1% of respondents. The most common forms of trauma resulting in PTSD included unexpected death of a loved one, sexual assault, and seeing someone badly injured or killed. In respondents meeting criteria for PTSD, the symptoms were chronic in nature, and associated with significant impairment and high rates of comorbidity. PTSD is a common psychiatric disorder in Canada. The results are surprising, given the comparably low rates of violent crime, a small military and few natural disasters. Potential implications of these findings are discussed. [ABSTRACT FROM AUTHOR]

Child maltreatment is associated with a huge burden of suffering, yet there are serious gaps in knowledge about its epidemiology and approaches to intervention. This article describes the development of a proposed national research framework in child maltreatment, as requested by the Department of Justice, Canada, based on (1) a review of the literature, (2) consultation with experts, and (3) application of evaluation criteria for considering research priorities. The article identifies gaps in knowledge about child maltreatment in Canada and proposes a research agenda to make evidence-based policy decisions more likely. Although this work was driven by gaps in Canada's knowledge about child maltreatment, the international scope of the review and consultation process could make the findings useful to broader research and policy audiences. [ABSTRACT FROM AUTHOR]

The diversity of tropical marine invertebrates is poorly documented, especially those groups for which collecting adults is difficult. We collected the planktonic tornaria larvae of hemichordates (acorn worms) to assess their hidden diversity in the Neotropics. Larvae were retrieved in plankton tows from waters of the Pacific and Caribbean coasts of Panama, followed by DNA barcoding of mitochondrial cytochrome c oxidase subunit I (COI) and 16S ribosomal DNA to estimate their diversity in the region. With moderate sampling efforts, we discovered six operational taxonomic units (OTUs) in the Bay of Panama on the Pacific coast, in contrast to the single species previously recorded for the entire Tropical Eastern Pacific. We found eight OTUs in Bocas del Toro province on the Caribbean coast, compared to seven species documented from adults in the entire Caribbean. All OTUs differed from each other and from named acorn worm sequences in GenBank by >10% pairwise distance in COI and >2% in 16S. Two of our OTUs matched 16S hemichordate sequences in GenBank: one was an unidentified or unnamed Balanoglossus from the Caribbean of Panama, and the other was an unidentified ptychoderid larva from the Bahamas. The species accumulation curves suggest that nearly all the species have been collected and only one more species might still remain undetected in the Pacific. In contrast, the Caribbean species accumulation curve suggests that further sampling could yield more than 10 additional OTUs. Tornaria from the 14 OTUs exhibited typical planktotrophic morphologies, and, in some cases, may be distinguished by differences in pigmentation and by the number of telotrochal ciliary bands, but in general, few diagnostic differences were detected. [ABSTRACT FROM AUTHOR]

Phoronid larvae, actinotrochs, are beautiful and complicated organisms which have attracted as much, if not more, attention than their adult forms. We collected actinotrochs from the waters of the Pacific and Caribbean coasts of Panama, and used DNA barcoding of mtCOI, as well as 16S and 18S sequences, to estimate the diversity of phoronids in the region. We discovered three operational taxonomic units (OTUs) in the Bay of Panama on the Pacific coast and four OTUs in Bocas del Toro on the Caribbean coast. Not only did all OTUs differ from each other by >10% pairwise distance in COI, but they also differed from all phoronid sequences in GenBank, including the four species for which adults have been reported for the Pacific of Panama, Phoronopsis harmeri, Phoronis psammophila, Phoronis muelleri, and Phoronis hippocrepia. In each ocean region, one common OTU was more abundant and occurred more frequently than other OTUs in our samples. The other five OTUs were relatively rare, with only one to three individuals collected during the entire project. Species accumulation curves were relatively flat but suggest that at least one more species is likely to be present at each site. Actinotrochs from the seven sequenced OTUs had morphologies typical of species with non‐brooded planktotrophic development and, in some cases, may be distinguished by differences in pigmentation and the arrangement of blood masses. We found one larva with morphology typical of brooded planktotrophic larvae for which sequencing failed, bringing the total number of potential species detected to eight and representing >50% of the adult species currently recognized globally. [ABSTRACT FROM AUTHOR]