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OBJECTIVE: Researchers employed two recruitment strategies in a school-based comparative effectiveness trial for students with a diagnosis of attention-deficit/hyperactivity disorder (ADHD) or autism. This study assessed the: 1) effectiveness of school-based referrals for identifying students meeting diagnostic criteria and 2) impact of eliminating requirements for existing diagnoses on recruitment, sample characteristics, and intervention response. METHOD: Autistic students and students with ADHD in schools serving underresourced communities were recruited for an executive functioning (EF) intervention trial over 2 years. In Year 1, school staff nominated students with previous diagnoses. In Year 2, school staff nominated students demonstrating EF challenges associated with ADHD or autism; previous diagnosis was not required. Study staff then confirmed diagnoses. RESULTS: More students were included in Year 2 (N = 106) than Year 1 (N = 37). In Year 2, 96% of students referred by school staff met diagnostic criteria for ADHD or autism, 53% of whom were not previously diagnosed. Newly identified students were less likely than previously diagnosed students to be receiving services and, for those with ADHD, were more likely to speak primarily Spanish at home. Previously diagnosed and newly identified students did not differ on other demographic variables or intervention response. Caregivers of previously diagnosed students reported more symptoms than caregivers of newly identified students for both diagnostic groups. Previously diagnosed students with ADHD had more researcher-rated symptoms than newly identified students. CONCLUSIONS: Recruitment for an intervention study using behavior-based referrals from school staff enhanced enrollment without compromising the sample's diagnostic integrity and engaged children who otherwise would have been excluded.
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BACKGROUND: Unstuck and On Target (UOT) is an executive function (EF) intervention for children with autism spectrum disorders (ASD) targeting insistence on sameness, flexibility, goal-setting, and planning through a cognitive-behavioral program of self-regulatory scripts, guided/faded practice, and visual/verbal cueing. UOT is contextually-based because it is implemented in school and at home, the contexts in which a child uses EF skills. METHODS: To evaluate the effectiveness of UOT compared with a social skills intervention (SS), 3rd-5th graders with ASD (mean IQ = 108; UOT n = 47; SS n = 20) received interventions delivered by school staff in small group sessions. Students were matched for gender, age, race, IQ, ASD symptomotolgy, medication status, and parents' education. Interventions were matched for 'dose' of intervention and training. Measures of pre-post change included classroom observations, parent/teacher report, and direct child measures of problem-solving, EF, and social skills. Schools were randomized and evaluators, but not parents or teachers, were blinded to intervention type. RESULTS: Interventions were administered with high fidelity. Children in both groups improved with intervention, but mean change scores from pre- to postintervention indicated significantly greater improvements for UOT than SS groups in: problem-solving, flexibility, and planning/organizing. Also, classroom observations revealed that participants in UOT made greater improvements than SS participants in their ability to follow rules, make transitions, and be flexible. Children in both groups made equivalent improvements in social skills. CONCLUSIONS: These data support the effectiveness of the first contextually-based EF intervention for children with ASD. UOT improved classroom behavior, flexibility, and problem-solving in children with ASD. Individuals with variable background/training in ASD successfully implemented UOT in mainstream educational settings.
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Trastornos Generalizados del Desarrollo Infantil/terapia , Terapia Cognitivo-Conductual/métodos , Función Ejecutiva , Niño , Trastornos Generalizados del Desarrollo Infantil/psicología , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas , Solución de Problemas , Instituciones Académicas , Habilidades Sociales , Resultado del Tratamiento , Escalas de WechslerRESUMEN
LAY ABSTRACT: Many autistic people struggle with mental health problems like anxiety, depression, inattention, and aggression, which can be challenging to treat. Executive function challenges, which impact many autistic individuals, may serve as a risk factor for mental health problems or make treating mental health conditions more difficult. While some people respond well to medication or therapy, others do not. This study tried to understand if there are different subgroups of autistic young people who may have similar patterns of executive function strengths and challenges-like flexibility, planning, self-monitoring, and emotion regulation. Then, we investigated whether executive function subgroups were related to mental health problems in autistic youth. We found three different types of executive function subgroups in autistic youth, each with different patterns of mental health problems. This helps us identify specific profiles of executive function strengths and challenges that may be helpful with identifying personalized supports, services, and treatment strategies for mental health conditions.
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Although circumscribed interests are pathognomonic with autism, much about these interests remains unknown. Using the Interests Scale (IS), this study compares interests between 76 neurotypical (NT) individuals and 109 individuals with high-functioning autism spectrum disorder (HF-ASD) matched groupwise on age, IQ, and gender ratio. Participants and their parents/caregivers completed diagnostic measures (the Autism Diagnostic Interview-Revised and the Autism Diagnostic Observation Schedule; HF-ASD only), cognitive tests (Wechsler IQ Scales), and questionnaires (the Repetitive Behavior Scale-Revised, the Behavior Rating Inventory of Executive Function, and the Social Responsiveness Scale), in addition to the IS. Consistent with previous research, HF-ASD and NT individuals did not differ in number of interest areas, but the types of interests and intensity of those interests differed considerably. Using only the IS intensity score, 81% of individuals were correctly classified (NT or HF-ASD) in a logistic regression analysis. Among individuals with HF-ASD, Interests Scale scores were significantly related to Autism Diagnostic Observation Schedule, Behavior Rating Inventory of Executive Function, Repetitive Behavior Scale-Revised, and Social Responsiveness Scale scores, but they were not related to Autism Diagnostic Interview-Revised scores, IQ, gender, age, or psychotropic medication use. The type and intensity, but not the number, of interests distinguish high-functioning individuals with ASD from NT individuals.
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Trastornos Generalizados del Desarrollo Infantil/psicología , Recreación/psicología , Adolescente , Niño , Función Ejecutiva , Humanos , Masculino , Pruebas Neuropsicológicas , Escalas de Valoración Psiquiátrica , Encuestas y Cuestionarios , Adulto JovenRESUMEN
The current study sought to characterize implicit bias toward children with autism and examine whether viewing educational materials about autism would change attitudes toward children with autism. A website developed by Sesame Street containing information about autism and resources for families was distributed to parents of children with autism (n = 473) and parents of children without autism (n = 707). Pre- and post-test measures of implicit bias toward children with autism; explicit attitudes and knowledge about autism; and parenting confidence, strain, and stigma were completed before and after the website was presented. Results indicated that parents of children with autism showed less implicit bias compared with those of non-autistic children during the pre-test, but the groups did not differ at the post-test. Parents without autistic children and those with more negative explicit attitudes showed a greater reduction in implicit bias from the pre- to the post-test. In addition, for parents of children with autism, a more positive change in explicit attitudes and increased knowledge from the pre- to the post-test was associated with more empowerment at the post-test. Together, our findings suggest that the online educational resources can reduce implicit bias against children with autism and help mitigate some of the psychological issues associated with parenting children with autism.
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Trastorno del Espectro Autista , Trastorno Autístico , Sesamum , Actitud , Niño , Humanos , PadresRESUMEN
Youth with autism spectrum disorder can face social-communication challenges related to sexuality, dating, and friendships. The purpose of this study was to assess the feasibility, acceptability, and preliminary efficacy of the Supporting Teens with Autism on Relationships program. In total, 84 youth with autism spectrum disorder aged 9 to 18 and their parents participated in this study; two groups received the Supporting Teens with Autism on Relationships program (interventionist-led parent group vs parent self-guided), while an attentional control group received a substance abuse prevention program that included instruction in problem-solving and social skills. Feasibility and acceptability of the Supporting Teens with Autism on Relationships program was high overall. The Supporting Teens with Autism on Relationships program was effective in increasing parent and youth knowledge of sexuality, while the attentional control was not. There was preliminary support for improvement in parenting efficacy related to discussing sexuality with their children. Gains were seen among completers regardless of whether the parent received support from a facilitator. Implications and future directions are discussed.
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Trastorno del Espectro Autista/psicología , Responsabilidad Parental/psicología , Evaluación de Programas y Proyectos de Salud/métodos , Educación Sexual/métodos , Conducta Sexual/psicología , Habilidades Sociales , Adolescente , Niño , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Padres/psicologíaRESUMEN
To promote knowledge and acceptance of autism, Sesame Workshop created an online initiative: See Amazing in All Children. This nationwide evaluation of See Amazing assessed whether it increased knowledge and acceptance, promoted community inclusion, reduced parenting strain, and enhanced parenting competence. Survey responses were collected online from parents of children (age ⩽ 6) with and without autism before (N = 1010), 1 week after (N = 510), and, for parents of autistic children, 1 month after (N = 182) they viewed the See Amazing materials. Following exposure, parents of non-autistic children showed small but significant increases in knowledge of autism and, like parents of autistic children, greater acceptance of autistic children. Parents of autistic children reported less strain, increased parenting competence, and more hope about involving their child in their community. That the See Amazing materials invoked positive changes in the general parent community and in parents of autistic children suggests that See Amazing materials have the potential to be an effective resource to increase acceptance and community inclusion, although limitations of self-selection, dropout rate, and lack of control group constrain interpretation. Implications include support for targeting acceptance as a step beyond awareness campaigns, though actual behavior change is a subject for future research.
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Trastorno del Espectro Autista/psicología , Medios de Comunicación de Masas , Padres/psicología , Distancia Psicológica , Estrés Psicológico/prevención & control , Estrés Psicológico/psicología , Adulto , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Masculino , Responsabilidad Parental/psicología , Encuestas y Cuestionarios , Estados UnidosRESUMEN
BACKGROUND: Youth with autism spectrum disorder (ASD) represent a growing population with significant service needs. Prominent among these needs are high rates of co-occurring psychiatric conditions that contribute to increased functional impairments and often necessitate mental health services. Executive functioning deficits are associated with ASD as well as common co-occurring conditions (e.g., attention-deficit/hyperactivity disorder) and an evidence-based intervention has been developed and tested to address executive functioning within the school context. There is an urgent need to implement indicated evidence-based interventions for youth with ASD receiving care in community mental health settings. Interventions that optimally "fit" the mental health services context as well as the complex and co-occurring mental health needs of these youth have the potential to improve key clinical outcomes for this high priority population. METHODS: This mixed-methods developmental study will apply the Exploration, Preparation, Implementation, Sustainment implementation framework and a community-academic partnership approach to systematically adapt and test an evidence-based executive functioning intervention for youth with ASD for delivery in community mental health settings. Specific aims are to (1) conduct a need and context assessment to inform the systematic adaptation an executive functioning evidence-based intervention; (2) systematically adapt the clinical intervention and develop a corresponding implementation plan, together entitled "Executive Functioning for Enhancing Community-based Treatment for ASD," (EFFECT for ASD); and (3) conduct a feasibility pilot test of EFFECT for ASD in community mental health settings. DISCUSSION: Tailoring evidence-based interventions for delivery in community-based mental health services for youth with ASD has the potential to increase quality of care and improve child outcomes. Results from the current study will serve as the foundation for large-scale hybrid implementation and effectiveness trials and a generalizable approach for different service systems of care and clinical populations. TRIAL REGISTRATION: Clinicaltrials.gov, NCT04295512.
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There is growing evidence of a camouflaging effect among females with autism spectrum disorder (ASD), particularly among those without intellectual disability, which may affect performance on gold-standard diagnostic measures. This study utilized an age- and IQ-matched sample of school-aged youth (n = 228) diagnosed with ASD to assess sex differences on the ADOS and ADI-R, parent-reported autistic traits, and adaptive skills. Although females and males were rated similarly on gold-standard diagnostic measures overall, females with higher IQs were less likely to meet criteria on the ADI-R. Females were also found to be significantly more impaired on parent reported autistic traits and adaptive skills. Overall, the findings suggest that some autistic females may be missed by current diagnostic procedures.
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Adaptación Psicológica/fisiología , Trastorno del Espectro Autista/diagnóstico , Trastorno del Espectro Autista/psicología , Caracteres Sexuales , Encuestas y Cuestionarios/normas , Adolescente , Estudios de Casos y Controles , Niño , Femenino , Humanos , Discapacidad Intelectual/diagnóstico , Discapacidad Intelectual/psicología , Masculino , Padres/psicologíaRESUMEN
Selective eating (often referred to as "picky" eating) is common in individuals with autism spectrum disorder (ASD) across the lifespan. Behavioral interventions are widely used to treat selective eating; however, most of these programs are time intensive, have not been evaluated for use in outpatient settings, and do not typically include youth beyond early childhood. Despite the functional impact and risk for negative outcomes associated with selective eating, there are no empirically supported treatments available for older children, adolescents, or adults, either with or without ASD. To address this treatment gap, we developed BUFFET: the Building Up Food Flexibility and Exposure Treatment program. BUFFET is a 14-week, multi-family group cognitive behavioral treatment for selective eating in children (8-12 years) with ASD. In this paper, we will (1) discuss the theoretical conceptualization of BUFFET, (2) describe the treatment content and structure, (3) present feasibility data from the initial pilot trial, and (4) consider next steps in treatment development.
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Trastorno del Espectro Autista/complicaciones , Terapia Cognitivo-Conductual/métodos , Trastornos de Alimentación y de la Ingestión de Alimentos/terapia , Desarrollo de Programa/métodos , Niño , Trastornos de Alimentación y de la Ingestión de Alimentos/etiología , HumanosRESUMEN
There is a lack of research examining differences in functioning in autism spectrum disorder (ASD) across ethnicity, particularly among those without intellectual disability (ID). This study investigated ethnic differences in parent-reported impairment in executive function, adaptive behavior, and social-emotional functioning. White and Black youth (n = 64; ages 6-17) with ASD without ID were compared on each of these domains. Black youth had significantly lower levels of impairment on all three domains. Findings may reflect better daily functioning among Black youth with ASD and/or cultural differences in parent response to questionnaires. Regardless, these findings raise concern about the sensitivity of commonly used measures for Black children with ASD and the impact of culture on daily functioning and symptom manifestation.
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Adaptación Psicológica , Trastorno del Espectro Autista/psicología , Población Negra/psicología , Función Ejecutiva , Padres , Ajuste Social , Población Blanca/psicología , Adolescente , Trastorno del Espectro Autista/diagnóstico , Femenino , Humanos , MasculinoRESUMEN
This study characterizes longitudinal change in adaptive behavior in 64 children and adolescents with autism spectrum disorder (ASD) without intellectual disability evaluated on multiple occasions, and examines whether prior estimate of executive function (EF) problems predicts future adaptive behavior scores. Compared to standardized estimates for their developmental stage, adaptive behavior in most participants was impaired and did not improve over time. Prior EF predicted later adaptive behavior in daily living skills and socialization domains after controlling for age and IQ. Self-monitoring behaviors robustly predicted later adaptive behavior in all domains (d = 0.60-0.94). Results support targeting treatment of adaptive skills in ASD, as well as the importance of assessing for EF problems that may contribute to adaptive behavior difficulties.
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Adaptación Psicológica , Trastorno del Espectro Autista/psicología , Función Ejecutiva , Actividades Cotidianas , Adolescente , Niño , Femenino , Humanos , Estudios Longitudinales , Masculino , Autocontrol/psicología , SocializaciónRESUMEN
Recent updates have been proposed to the Autism Diagnostic Observation Schedule-2 Module 4 diagnostic algorithm. This new algorithm, however, has not yet been validated in an independent sample without intellectual disability (ID). This multi-site study compared the original and revised algorithms in individuals with ASD without ID. The revised algorithm demonstrated increased sensitivity, but lower specificity in the overall sample. Estimates were highest for females, individuals with a verbal IQ below 85 or above 115, and ages 16 and older. Best practice diagnostic procedures should include the Module 4 in conjunction with other assessment tools. Balancing needs for sensitivity and specificity depending on the purpose of assessment (e.g., clinical vs. research) and demographic characteristics mentioned above will enhance its utility.
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Algoritmos , Trastorno Autístico/diagnóstico , Adolescente , Adulto , Niño , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Femenino , Humanos , Persona de Mediana EdadRESUMEN
We examined prospective cohort studies evaluating the relation between prenatal and neonatal exposure to polychlorinated biphenyls (PCBs) and neurodevelopment in children to assess the feasibility of conducting a meta-analysis to support decision making. We described studies in terms of exposure and end point categorization, statistical analysis, and reporting of results. We used this evaluation to assess the feasibility of grouping studies into reasonably uniform categories. The most consistently used tests included Brazelton's Neonatal Behavioral Assessment Scale, the neurologic optimality score in the neonatal period, the Bayley Scales of Infant Development at 5-8 months of age, and the McCarthy Scales of Children's Abilities in 5-year-olds. Despite administering the same tests at similar ages, the studies were too dissimilar to allow a meaningful quantitative examination of outcomes across cohorts. These analyses indicate that our ability to conduct weight-of-evidence assessments of the epidemiologic literature on neurotoxicants may be limited, even in the presence of multiple studies, if the available study methods, data analysis, and reporting lack comparability.
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Sistema Nervioso/efectos de los fármacos , Sistema Nervioso/crecimiento & desarrollo , Síndromes de Neurotoxicidad/etiología , Bifenilos Policlorados/efectos adversos , Preescolar , Toma de Decisiones , Humanos , Lactante , Recién Nacido , Masculino , Metaanálisis como Asunto , Literatura de Revisión como AsuntoRESUMEN
The ability to conduct weight-of-evidence assessments to inform the evaluation of potential environmental neurotoxicants is limited by lack of comparability of study methods, data analysis, and reporting. There is a need to establish consensus guidelines for conducting, analyzing, and reporting neurodevelopmental environmental epidemiologic studies, while recognizing that consistency is likewise needed for epidemiology studies examining other health outcomes. This paper proposes a set of considerations to be used by the scientific community at-large as a tool for systematically evaluating the quality of proposed and/or published studies in terms of their value for weight-of-evidence assessments. Particular emphasis is placed on evaluating factors influencing the risk of incorrect conclusions at the level of study findings. The proposed considerations are the first step in what must be a larger consensus-based process and can serve to catalyze such a discussion. Achieving consensus in these types of endeavors is difficult; however, opportunities exist for further interdisciplinary discussion, collaboration, and research that will help realize this goal. Broad acceptance and application of such an approach can facilitate the expanded use of environmental epidemiology studies of potential neurodevelopmental toxicants in the protection of public health, and specifically children's health.
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Investigación Biomédica/métodos , Contaminantes Ambientales/toxicidad , Guías como Asunto , Sistema Nervioso/efectos de los fármacos , Efectos Tardíos de la Exposición Prenatal/epidemiología , Efectos Tardíos de la Exposición Prenatal/fisiopatología , Animales , Interpretación Estadística de Datos , Femenino , Humanos , Sistema Nervioso/embriología , Sistema Nervioso/crecimiento & desarrollo , EmbarazoRESUMEN
BACKGROUND: Epidemiologic weight-of-evidence reviews to support regulatory decision making regarding the association between environmental chemical exposures and neurodevelopmental outcomes in children are often complicated by lack of consistency across studies. OBJECTIVE: We examined prospective cohort studies evaluating the relation between prenatal and neonatal exposure to polychlorinated biphenyls (PCBs) and neurodevelopment in children to assess the feasibility of conducting a meta-analysis to support decision making. DATA EXTRACTION/SYNTHESIS: We described studies in terms of exposure and end point categorization, statistical analysis, and reporting of results. We used this evaluation to assess the feasibility of grouping studies into reasonably uniform categories. RESULTS: The current literature includes 11 cohorts of children for whom effects from prenatal or neonatal PCB exposures were assessed. The most consistently used tests included Brazelton's Neonatal Behavioral Assessment Scale, the neurologic optimality score in the neonatal period, the Bayley Scales of Infant Development at 5-8 months of age, and the McCarthy Scales of Children's Abilities in 5-year-olds. Despite administering the same tests at similar ages, the studies were too dissimilar to allow a meaningful quantitative examination of outcomes across cohorts. CONCLUSIONS: These analyses indicate that our ability to conduct weight-of-evidence assessments of the epidemiologic literature on neurotoxicants may be limited, even in the presence of multiple studies, if the available study methods, data analysis, and reporting lack comparability. Our findings add support to previous calls for establishing consensus standards for the conduct, analysis, and reporting of epidemiologic studies in general, and for those evaluating the effects of potential neurotoxic exposures in particular.
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Contaminación Ambiental/legislación & jurisprudencia , Regulación Gubernamental , Metaanálisis como Asunto , Neurotoxinas/toxicidad , Formulación de Políticas , Bifenilos Policlorados/toxicidad , Literatura de Revisión como Asunto , Femenino , Humanos , Recién Nacido , Exposición Materna , Sistema Nervioso/efectos de los fármacos , Sistema Nervioso/crecimiento & desarrolloRESUMEN
With research suggesting increasing incidence of pediatric neurodevelopmental disorders, questions regarding etiology continue to be raised. Neurodevelopmental function tests have been used in epidemiology studies to evaluate relationships between environmental chemical exposures and neurodevelopmental deficits. Limitations of currently used tests and difficulties with their interpretation have been described, but a comprehensive critical examination of tests commonly used in studies of environmental chemicals and pediatric neurodevelopmental disorders has not been conducted. We provide here a listing and critical evaluation of commonly used neurodevelopmental tests in studies exploring effects from chemical exposures and recommend measures that are not often used, but should be considered. We also discuss important considerations in selecting appropriate tests and provide a case study by reviewing the literature on polychlorinated biphenyls.
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Discapacidades del Desarrollo/diagnóstico , Exposición a Riesgos Ambientales , Pruebas Neuropsicológicas , Síndromes de Neurotoxicidad/diagnóstico , Psicometría , Trastornos Relacionados con Sustancias/diagnóstico , Niño , Cultura , Discapacidades del Desarrollo/inducido químicamente , Estudios Epidemiológicos , Humanos , Reproducibilidad de los Resultados , Factores de RiesgoRESUMEN
In this paper, we review the most recent and often conflicting findings on conventional measures of executive control in autism spectrum disorders. We discuss the obstacles to accurate measurement of executive control, such as: its prolonged developmental trajectory; lack of consensus on its definition and whether it is a unitary construct; the inherent complexity of executive control; and the difficulty measuring executive-control functions in laboratory or clinical settings. We review the potential of an ecological-validity framework to address some of these problems, and describe new tests claiming verisimilitude, or close resemblance to "real life" demands. We also review the concept of veridicality, which allows for the measurement of the ecological validity of any task, and discuss the few studies addressing ecological validity in individuals with autism. Our review suggests that a multi-source approach emphasizing veridicality may provide the most comprehensive assessment of executive control in autism.
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Trastorno Autístico/fisiopatología , Solución de Problemas/fisiología , Medio Social , Trastorno Autístico/diagnóstico , Humanos , Pruebas NeuropsicológicasRESUMEN
We examined prospective cohort studies evaluating the relation between prenatal and neonatal exposure to polychlorinated biphenyls (PCBs) and neurodevelopment in children to assess the feasibility of conducting a meta-analysis to support decision making. We described studies in terms of exposure and end point categorization, statistical analysis, and reporting of results. We used this evaluation to assess the feasibility of grouping studies into reasonably uniform categories. The most consistently used tests included Brazelton's Neonatal Behavioral Assessment Scale, the neurologic optimality score in the neonatal period, the Bayley Scales of Infant Development at 5-8months of age, and the McCarthy Scales of Children's Abilities in 5-year-olds. Despite administering the same tests at similar ages, the studies were too dissimilar to allow a meaningful quantitative examination of outcomes across cohorts. These analyses indicate that our ability to conduct weight-of-evidence assessments of the epidemiologic literature on neurotoxicants may be limited, even in the presence of multiple studies, if the available study methods, data analysis, and reporting lack comparability.
Foram examinados estudos de grupo que avaliaram a relação entre a exposição pré-natal e neonatal aos bifenilos policlorados (PCB) e o desenvolvimento neuropsicomotor em crianças a fim de avaliar a viabilidade da realização de uma meta-análise para suporte à tomada de decisão. Nós descrevemos os estudos em termos de exposição, categorizações, análise estatística e elaboração de relatórios de resultados. Nós utilizamos esta avaliação para verificar a viabilidade de agrupar os estudos em categorias razoavelmente uniformes. Os testes mais utilizados foram Brazelton Neonatal Behavioral Assessment Scale, a pontuação de otimalidade neurológica no período neonatal, as Escalas Bayley de Desenvolvimento Infantil de 5 a 8 meses de idade, e as Escalas McCarthy de habilidades das crianças em 5 anos de idade. Apesar de administrar os mesmos testes com idades semelhantes, os estudos foram muito diferentes para permitir uma análise quantitativa significativa dos resultados entre grupos. Estas análises indicam que a nossa capacidade de realizar avaliações da literatura epidemiológica sobre neurotóxicos pode ser limitada - mesmo na presença de vários estudos - se não existe nenhuma forma de comparação com os métodos de estudo disponíveis e análise dos dados.