A prospective study of childhood emotional and behavioural problems in Port Pirie, South Australia

Tracing the long-term legacy of childhood lead exposure: a review of three decades of the port Pirie cohort study

Several prospective cohort studies have demonstrated that childhood lead levels show small but statistically significant adjusted associations with subsequent development in later childhood and adolescence. The Port Pirie Cohort study is one of the few prospective cohort studies to follow participants into adulthood. This paper reviews all childhood and adulthood findings of the Port Pirie Cohort study to date. Cohort members (initially, 723 infants born in/around the lead-smelting town of Port Pirie) showed a wide range of childhood blood lead levels, which peaked around 2 years old (M=21.3μg/dL, SD=1.2). At all childhood assessments, postnatal lead levels - particularly those reflecting cumulative exposure - showed small significant associations with outcomes including cognitive development, IQ, and mental health problems. While associations were substantially attenuated after adjusting for several childhood covariates, many remained statistically significant. Furthermore, average childhood blood lead showed small significant associations with some adult mental health problems for females, including anxiety problems and phobia, though associations only approached significance following covariate adjustment. Overall, there did not appear to be any age of greatest vulnerability or threshold of effect, and at all ages, females appeared more susceptible to lead-associated deficits. Together, these findings suggest that the associations between early childhood lead exposure and subsequent developmental outcomes may persist. However, as the magnitude of these effects was small, they are not discernible at the individual level, posing more of a population health concern. It appears that the combination of multiple early childhood factors best predicts later development. As such, minimising lead exposure in combination with improving other important early childhood factors such as parent-child interactions may be the best way to improve developmental outcomes.

Multicultural assessment of child and adolescent psychopathology with ASEBA and SDQ instruments: research findings, applications, and future directions

Around the world, cultural blending and conflict pose challenges for assessment and understanding of psychopathology. Economical, evidence-based, culturally robust assessment is needed for research, for answering public health questions, and for evaluating immigrant, refugee, and minority children. This article applies multicultural perspectives to behavioral, emotional, and social problems assessed on dimensions describing children's functioning, as rated by parents, teachers, children, and others. The development of Achenbach System of Empirically Based Assessment (ASEBA) and Strengths and Difficulties Questionnaire (SDQ) forms and their applications to multicultural research are presented. A primary aim of both questionnaires is to identify children at high risk of psychiatric disorders and who therefore warrant further assessment. The forms are self-administered or administered by lay interviewers. ASEBA problem items are scored on 6 DSM-oriented scales and 3 broader band scales, plus 8 syndromes derived statistically as taxonomic constructs and supported by uniform confirmatory factor analyses of samples from many populations. Comparisons of ASEBA scale scores, psychometrics, and correlates are available for diverse populations. SDQ forms are scored on one broad-band scale and 5 a priori behavioral dimensions supported by data from various populations. For both instruments, factor analyses, psychometrics, and correlates are available for diverse populations. The willingness and ability of hundreds of thousands of respondents from diverse groups to complete ASEBA and SDQ forms support this approach to multicultural assessment. Although particular items and scales may have differential relevance among groups and additional assessment procedures are needed, comparable results are found in many populations. Scale scores vary more within than between populations, and distributions of scores overlap greatly among different populations. Ratings of children's problems thus indicate more heterogeneity within populations than distinctiveness between populations. Norms from multiple populations can be used to compare children's scores with relevant peer groups. Multicultural dimensional research can advance knowledge by diversifying normative data; by comparing immigrant children with nonimmigrant compatriots and with host country children; by identifying outlier findings for elucidation by emic research; and by fostering efforts to dimensionalize DSM-V diagnostic criteria.

Protecting children from toxic exposure: three strategies

To a toxicologist, "poisonings" are cases in which the child has a defined pattern of symptoms, corresponding to toxic effects at a mid to high level of exposure. "Toxicity" refers to a broader spectrum of effects. At lower levels of toxicity a child may have no specific, individual symptoms but may be affected subclinically. There are three basic strategies to protect children: individual intervention, the preventive medicine strategy, and the public health strategy. This article uses lead exposure as a model for discussing these differences in terminology and the three different protective strategies.