David R. Offord

Epidemiology of Childhood Depressive Disorders: A Critical Review

The methodology of 14 recent epidemiological studies of childhood and adolescent depressive disorders was critically reviewed and findings summarized for prevalence, comorbidity, correlates, risk factors, and outcome. Shortcomings in sampling and considerable inconsistency in the measurement of depression in the studies made it difficult to draw firm conclusions about the prevalence and correlates of depression in young people. Nonetheless, it is likely that major depressive disorder is relatively uncommon in prepubertal children, increases in frequency in adolescents, and is significantly associated with such variables as family dysfunction and low self-esteem. Comorbidity of depression with other psychiatric disorders was also high in these nonpatient samples and it will be important in future work to assess the implications of this for the etiology, treatment, and prognosis of depressive disorders in children and adolescents.

Stress, social support and depression in single and married mothers.

Background: This study examined the effect of stress and social support on the relationship between single-parent status and depression. Method: A secondary data analysis of the 1994–95 National Population Health Survey was conducted. Single and married mothers who participated in the survey were derived from the general sample (N = 2,921). Logistic regression techniques were used to assess the mediating and moderating effects of stress and social support on the relationship between family structure and depression. Results: Bivariate analyses showed that, compared to married mothers, single mothers were more likely to have suffered an episode of depression (12-month prevalence), to report higher levels of chronic stress, more recent life events and a greater number of childhood adversities. Single mothers also reported lower levels of perceived social support, social involvement and frequency of contact with friends and family than married mothers. The results of the multivariate analyses showed that, together, stress and social support account for almost 40% of the relationship between single- parent status and depression. We also found a conditional effect of stress on depression by family structure. Life events were more strongly related to depression in married than in single mothers. Conclusions: A substantial part of the association between single-parent status and depression can be accounted for by differences in exposure to stress and social support.Our results suggest that it is important to examine multiple sources of stress, as exposure to both distal and proximal stressors were higher among single mothers. Limitations and directions for future research are discussed.

Integrating Assessment Data from Multiple Informants

OBJECTIVE To examine the consequences for measurement of child psychiatric disorder (conduct and oppositional disorders) of not integrating the data on the same individual from different informants compared with integrating the information from parents and teachers, using three different strategies. METHOD Data for the study came from problem checklist assessments done by parents and teachers of children aged 6 to 16 years (N = 1,134) selected with known probability from a general population sample and from structured interviews obtained in a stratified random subsample (n = 251). RESULTS As expected, parent-teacher agreement was low. The pattern of associated features of disorder was found to vary markedly in parent-identified compared with teacher-identified disorder. Furthermore, combining informants had the disadvantage of masking the distinctive patterns of associated features noted in informant-specific disorders. Finally, by treating disorder as informant-specific, the internal properties of the measure are not generally inferior to those obtained by combining informants in various ways. CONCLUSION Child psychiatric disorders should be conceptualized as informant-specific phenomena.

One-Year Prevalence of Psychiatric Disorder in Ontarians 15 to 64 Years of Age

Objective: To present the one-year prevalence of 14 psychiatric disorders in a community sample of Ontarians aged 15 to 64 years. Method: Data on psychiatric disorders were collected on 9953 respondents using the University of Michigan revision of the Composite International Diagnostic Interview (UM-CIDI). DSM-III-R criteria were used to define the psychiatric disorders. Results: Almost 1 in 5 Ontarians (18.6%) had one or more of the disorders measured in the survey. Among 15- to 24-year-olds, 1 in 4 was affected. The distribution of individual disorders varied by sex and age. Conclusion: Because of the immense burden of suffering associated with psychiatric disorders, clinical and research efforts in this area should receive high priority within the health budget.

Outcome, prognosis, and risk in a longitudinal follow-up study.

This study reports the results of a 4-year follow-up of a community sample of children who were ages 4 to 12 in 1983 at the first wave of data collection. Results on outcomes revealed that conduct disorder showed the greatest stability especially from late childhood to early adolescence. In multivariate analyses, both family dysfunction and problems getting along with others significantly predicted the persistence of one or more psychiatric disorders 4 years later, and low income predicted one or more psychiatric disorders among children free of disorder 4 years earlier. The implications of the results for the child psychiatric field, especially prevention, are discussed.

Ontario Child Health Study: Correlates of Disorder

Data from the Ontario Child Health Study were used to examine the prevalence and selected correlates of conduct disorder, hyperactivity, emotional disorder, and somatization in children 4 to 16 years of age by informant (parent and teacher for children 4 to 11, and parent and youth for children 12 to 16). The results indicate that the prevalence and pattern of correlates of the individual disorders differ in important ways by informant. This suggests that we need to understand the factors that influence assessments provided by informants from different contexts (e.g., parents and teachers) before combining information from them to arrive at singular classifications.

Contributions of risk-factor research to developmental psychopathology.

Risk-factor research refers to the study of antecedent conditions and subsequent outcomes and the ways in which these are interrelated. The research encompasses a broad range of questions and research strategies. The paper discusses the characteristics and contributions of risk-factor research in the context of developmental psychopathology. The ways in which causal paths are conceptualized, the capacity to integrate multiple influences, and applications that can be derived from the findings are discussed. The progression of research is illustrated in relation to key concepts (correlate, risk factor, marker, causal risk factor) that reflect varied levels of understanding antecedent-outcome relations. The identification of causal relations, progressions, and paths over the course of development and the interplay of theory, research, and application are illustrated and discussed.

Lowering the Burden of Suffering From Child Psychiatric Disorder: Trade‐Offs Among Clinical, Targeted, and Universal Interventions

OBJECTIVE To examine the trade-offs among clinical, targeted, and universal interventions aimed at lowering the burden of suffering from child psychiatric disorders. METHOD Data from clinical and research studies were organized to show the advantages and disadvantages of the three strategies. RESULTS Important trade-offs exist among these three approaches. The strategy to reduce the burden of suffering from child psychiatric disorder should consist of a number of concurrent steps. First, effective universal programs should be in place. Targeted programs should follow for those not helped sufficiently by the universal programs. Finally, for those unaffected by the targeted programs, clinical services should be available. CONCLUSION An optimal mix of universal, targeted, and clinical programs is needed. The nature of the combination will change as knowledge accumulates, and there will always be trade-offs among these three. Acad.

Summary of selected results

Selected results from the Ontario Child Health Study (OCHS), a cross-sectional community survey of Ontario children four to 16 years of age, are presented in the areas of prevalence, risk indicators and service utilization. The six month prevalence of one or more of four psychiatric disorders (conduct disorder, hyperactivity, emotional disorder, and somatization), in children four to 16 years of age, in Ontario was 18.1%. The highest rate was in 12 to 16 year old girls, and the lowest rate in four to 11 year old girls. Co-morbidity among these four disorders was high while the proportion of disorders identified by more than one respondent was low. Psychiatric disorders co-occurred significantly with other morbidities in children, including poor school performance, chronic health problems, substance use and suicidal behaviour. Chronic medical illness in the child as well as single parent status, living in a family on social assistance and residing in subsidized housing, were all strong indicators of increased rates of psychiatric disorders in children. Specialized mental health/social services, over a six month period, reached fewer than one of five children with psychiatric disorders, as measured in the study. In contrast, ambulatory medical care (primarily visits to family doctors and pediatricians) served almost 60% of Ontario children four to 16 years old, over the same six month period. The results are compared with those in the literature.

ADDH and Conduct Disorder: Degree of Diagnostic Overlap and Differences among Correlates

The objective of this paper was to determine the degree of diagnostic overlap between attention deficit disorder with hyperactivity (ADDH) and conduct disorder (CD) and to see whether ADDH children show a different pattern of demographic, familial, and developmental correlates compared to CD children. The sample for this study consisted of 2,697 4- to 16-year-olds who participated in the Ontario Child Health Study. In terms of diagnostic overlap, ADDH and CD occurred together more often than by chance alone, particularly among girls. Pure groups of ADDH and CD children differed in a variety of ways. In general, ADDH children were younger and had experienced more developmental delays and less psychosocial disadvantage than the CD children. No differences were found with respect to associated impairments, a measure of severity. Children with both ADDH and CD (a mixed group) appeared to represent a true hybrid disorder rather than one diagnosis or the other. These findings support the validity of ADDH compared to CD, at least in terms of the pattern of correlates.