Biomedical subjects

D R Offord

Publications and source records attributed to D R Offord.

At least 19 recordsLinked to original sources

PubMed1992

Ontario child health study: social and school impairments in children aged 6 to 16 years.

This study reports on informant-specific prevalence rates and the relationship with psychiatric disorder of social and school impairments in a community sample of children, 6 to 16 years of age, in Ontario. Prevalence rates ranged from less than 1% to over 18% depending on informant, and there was a low level of agreement between informants. Although impairments were strongly related to psychiatric disorder, there were many children with impairments and no psychiatric disorder or psychiatric disorder with no impairments. Implications of these results are discussed.

Adolescent↗

PubMed1992

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.

Adolescent↗

PubMed1992

Predicting substance use in late adolescence: results from the Ontario Child Health Study follow-up.

OBJECTIVE: The purpose of this study was to evaluate the relationship between use of tobacco, alcohol, marijuana, and hard drugs (substance use) and psychiatric disorder in early adolescence and substance use in late adolescence. METHOD: Adolescents included in the study were identified by means of a household sampling frame and participated in the Ontario Child Health Study in 1983 and the follow-up in 1987. There were 726 12-16-year-olds (369 boys and 357 girls) in 1983 who had complete information in 1987. Data on substance use were collected from adolescents by using a structured, self-administered questionnaire. Data on psychiatric disorder were collected in 1983 from both adolescents and their parents by using problem checklists to assess conduct disorder, attention deficit disorder, and emotional disorder. RESULTS: Prior substance use in 1983 was associated strongly with subsequent use in 1987. Among the psychiatric disorders assessed in 1983, only conduct disorder made an independent contribution to predicting use of marijuana (relative odds = 3.46) and other hard drugs (relative odds = 6.82) in 1987, after prior use of these substances and coexisting attention deficit and emotional disorders were controlled. Corresponding estimates of attributable risk (the expected contribution of exposure to conduct disorder to the development of substance use) were 5.7% and 11.1%, respectively. CONCLUSIONS: Although a statistically significant relationship existed between conduct disorder in early adolescence and use of marijuana and hard drugs in late adolescence, the potential is limited for preventing substance use in the general population by treating conduct disorder early on.

Adolescent↗

PubMed1992

Psychiatric disorders in adopted children: a profile from the Ontario Child Health Study.

Studies of clinical populations suggest that adopted children are overrepresented among children using mental health facilities, whereas studies using non clinical populations of adopted children have reached mixed conclusions about whether or not there is an increased psychological risk associated with adoption. Data from the Ontario Child Health Study, a community survey of children aged four to 16 years, which included a subpopulation of adopted children, were used to: 1. profile the characteristics of adoptive families; 2. examine the strength of adoptive status as a marker for psychiatric and educational morbidity; and 3. determine the extent to which adoptive status has an independent relationship with psychiatric and educational morbidities. The findings were: 1. adoptive mothers were significantly older than non adoptive mothers, but otherwise adoptive families did not differ significantly from non adoptive families, 2. adoption in boys, but not in girls, was a significant marker for psychiatric disorder and poor school performance; adoption in adolescent girls was a significant marker for substance use; and 3. multivariate analyses demonstrated no independent effect of adoption on psychiatric disorder or poor school performance; for adolescents, adoptive status did have an independent relationship with substance use for girls. The implications of these findings will be discussed.

Achievement↗

PubMed1991

Ontario Child Health Study follow-up: evaluation of sample loss.

This article presents an analysis of sample loss in a 4-year follow-up of children aged 4 to 12 who participated in the Ontario Child Health Study in 1983. Of the 1,617 children participating in the original Ontario Child Health Study, 1,172 (72.5%) were located and enlisted at follow-up in 1987. Based on wave-one assessments, nonparticipants at follow-up tended to have higher levels of psychopathology and family risk variables. Respondents were matched with nonparticipants and differentially weighted to compensate for selective loss. In comparing estimates based on actual (observed) and weighted responses in the follow-up sample, it was found that the effects of sample loss depended on the analytical focus. Evaluations of outcome of disorder and risk for disorder were not affected by sample loss. Evaluation of variables that predict persistence of disorder (prognosis) was affected by a bias toward the null.

Bias↗

PubMed1991

A dose-response analysis of the effects of methylphenidate on the peer interactions and simulated classroom performance of ADD children with and without conduct problems.

To examine the social effects of methylphenidate, groups of 15 attention-deficit disordered boys with (ADD) and 15 ADD boys without conduct problems (ADD/CP) were paired with normal peers. ADD and ADD/CP children showed a different pattern of responses to methylphenidate. While on task behavior in ADD/CP dyads increased at 0.15 mg/kg doses, increases in ADD dyads were not observed until doses reached 0.50 mg/kg. Although controlling interaction in ADD children decreased at 0.15 mg/kg, the controlling behavior of ADD/CP children did not decline at either dose. Peers of both ADD and ADD/CP children showed reciprocal declines in controlling behavior. In both free play and cooperative task situations, 0.15 mg/kg increased social interaction in ADD boys and decreased social interaction in ADD/CP boys.

Achievement↗

PubMed1991

Psychiatric disorder and substance use in adolescence.

This article examines the relationship between psychiatric disorder and the use of tobacco, alcohol, marijuana and hard drugs during adolescence. The sample of 1,302 adolescents aged 12 to 16 came from households selected by stratified, cluster and random sampling of the 1981 Canada Census. Symptom checklists were used to approximate diagnoses of conduct disorder, attention deficit disorder and emotional disorder. Logistic regression analyses indicated that conduct disorder was strongly related to all types of substance use and that emotional disorder was related to the use of tobacco, alcohol and hard drugs. These relationships were true for the adolescents' self-assessments only; the parents' assessments of psychiatric disorder were not related to the adolescents' reports of substance use.

Adolescent↗

PubMed1991

Prevalence of behavioral symptoms and the relationship of child, parent, and family variables in 4- and 5-year-olds: results from the Ontario Child Health Study.

This study presents the frequency of behavioral symptoms in 4- and 5-year-old children as reported by parents in the Ontario Child Health Study. It also examines the relationship of the presence of child, parent, and family variables with parent-reported total scale scores. Eight of the 135 items were reported to be present by the parents of 50% or more of the 437 children in the sample. For 18 items, the prevalence rates for boys were significantly higher than for girls. Multiple regression analysis resulted in slightly different child, parent, and family variables influencing scores when total scores and scores on severe items only were used as dependent variables. Two variables appeared in both models: general health of the child and family status. Some of the child, parent, and family variables found to be associated with behavior disorder in older children do not appear to have as strong an association with disorder in 4- and 5-year-olds.

Canada↗

PubMed1991

Children with chronic illness: family and parent demographic characteristics and psychosocial adjustment.

This paper presents the results of an epidemiologic study that compares and contrasts psychosocial characteristics of parents and family units of children with chronic illness or physical disability (chronic health problems) with those of healthy children. Data were derived from the Ontario Child Health Study of 1869 randomly selected families, with 3294 children aged 4 to 16 years. In the absence of significant differences between parents and families of children with chronic illness alone and those with physical disability, these groups were combined for analysis, for which odds ratios (OR) or t tests were used. Significant positive findings included increased rates of parental treatment for "nerves" (mothers' OR = 2.1, fathers' OR = 1.9) and increased maternal negative affect scores (Bradburn Affect Balance Scale) (P less than .001) among parents of children with chronic health problems. Important negative findings (95% confidence interval of the OR included 1) included no increase in single-parent families (OR = 1.2), social isolation (OR = 1.0), or alcohol problems (OR = 1.2) among parents of children with chronic health problems. Categorically defined family dysfunction did not differ between the two groups (OR = 1.1). These data contrast with several clinic-based studies and suggest that, in a widely generalizable population survey, families of children with chronic health problems including physical disability do not suffer a marked excess of dysfunction, although some indicators of individual parent psychosocial problems were modestly elevated.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1990

Prevention of suicide.

We reviewed the epidemiologic features of suicide in Canada and evaluated suicide prevention programs. Three groups were found to be at increased risk for suicide: men aged 70 years or more, women aged 65 to 69 and men aged 20 to 24. The other groups, in decreasing order of risk, were the mentally ill, people who have attempted suicide, those with a life-threatening illness, native people, people with a family history of suicide and prisoners. Studies that evaluated suicide prevention programs showed that none significantly reduced the incidence of suicide; however, the studies were found to be methodologically inadequate or used noncomparable systems of data collection. On the basis of our findings we recommend that primary care physicians routinely evaluate suicide risk among patients in high-risk groups and that intervention include counselling, follow-up and, if necessary, referral to a psychiatrist. Close follow-up is recommended for newly discharged psychiatric patients and those who recently attempted suicide.

Adolescent↗

PubMed1990

Primary prevention of conduct disorder: issues and prospects.

This research seeks to advance our understanding of the primary prevention of conduct disorder in three ways: (1) by illustrating how type of analysis and research design may influence our evaluation of a variable as a potential risk factor; (2) by examining the implications for primary prevention of choosing multiple risk factors for modification; and (3) by comparing the advantages and disadvantages of intervening with children living in high-risk situations versus children in the general population. The analyses are based on 1,001 children aged 6 to 12 in 1983 who participated in the original Ontario Child Health Study and follow-up. The results show that (1) inattention to type of analysis and research design may lead to false inferences about the usefulness of a hypothesized risk factor; (2) selecting multiple risk factors for modification increases the potential program benefits in prevention; and (3) primary prevention demonstration projects, to be evaluable at reasonable cost, must focus on children living in high-risk situations.

Achievement↗

PubMed1990

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.

Adolescent↗

PubMed1990

The prevalence of overanxious disorder and separation anxiety disorder: results from the Ontario Child Health Study.

Data from a community epidemiological study of 1,869 families (Ontario Child Health Study) was used to evaluate the effect of different ways of operationalizing DSM-III-R criteria for overanxious disorder (OAD) and separation anxiety disorder (SAD) among adolescents aged 12 to 16. The authors determined that a high threshold for symptoms to qualify as present, the presence of one or both of the essential symptoms, and the presence of four or more auxiliary symptoms for OAD and three or more for SAD gave prevalence of OAD of 3.6% and SAD of 2.4%. There was high overlap between the presence of OAD and SAD and externalizing disorder and depression, but one-half of youth with OAD and SAD had pure anxiety disorder. Youth with OAD and SAD were just as impaired as youth with externalizing disorder and depression, except that they admitted to less social isolation and their schoolwork was less affected.

Adolescent↗

PubMed1990

The clinical significance of neurocognitive impairments among children with psychiatric disorders: diagnosis and situational specificity.

The overall objective of this paper is to assess the clinical significance of neurocognitive impairments (NCI) among children with psychiatric disorders. One hundred and fifty-three children referred to a mental health clinic underwent neuropsychological testing. Their parents were interviewed to obtain background information and data on their children's behavior. Parents and teachers also filled out behavior checklists. The results suggest that neurocognitive impairments are: (1) more strongly associated with externalizing rather than internalizing psychiatric diagnoses; and (2) are correlated with psychiatric symptoms at school, but not at home. The implications for understanding the impact of neurocognitive impairments on the situational specificity of psychiatric symptoms are discussed.

Affective Symptoms↗

PubMed1990

Correlates of emotional disorder from a community survey.

This report examines the correlates of emotional disorder (ED) for children in the community. The following models were used to examine the correlates of ED: 1. the variables predicting the presence or absence of ED; 2. the variables predicting the presence or absence of ED when controlling for coexisting hyperactivity and conduct disorder; and 3. the correlates of pure ED versus pure hyperactivity, and pure ED versus pure conduct disorder. Data from the Ontario Child Health Study, a community survey of children aged four to 16 years in the province of Ontario, were used. Many of the correlates proposed in the literature as variables that differentiate children with ED from normal children were supported using the first two models. Only one correlate was found which differentiated pure ED from pure hyperactivity, and no correlates differentiated children with pure ED from children with pure conduct disorder.

Adolescent↗

PubMed1989

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.

Adolescent↗

PubMed1989

Correlates, associated impairments and patterns of service utilization of children with attention deficit disorder: findings from the Ontario Child Health Study.

The objective of this paper is to report on the correlates of attention deficit disorder with hyperactivity (ADDH), the associated impairments of ADDH children, and to describe briefly their utilization of services. Our results suggest that household, family, parental, and developmental variables are associated with this disorder. However, child-centered, rather than psychosocial, variables emerge as important if one controls for the presence of other disorders. Compared to children without any disorder, ADDH children are also impaired in their relationships with others, their school performance, and competence in extra-curricular activities. ADDH children utilized mental health, social, and special education services more than non-ADDH children. Nevertheless, it was found that only a minority of ADDH children had received specialized mental health or social services in the past 6 months.

Achievement↗

PubMed1989

Ontario Child Health Study: prevalence of attention deficit disorder with hyperactivity.

The objective of this paper is to present data from the Ontario Child Health Study on the prevalence of attention deficit disorder with hyperactivity (ADDH). The overall prevalence of ADDH was 9.0% in boys and 3.3% in girls. There were no significant differences in the prevalence of ADDH by age or urban-rural status, but the disorder was significantly more common in boys than in girls. The prevalence of various subtypes of ADDH was also explored: attention deficit with and without hyperactivity, situational vs pervasive ADDH, and ADDH with and without other disorders. The clinical implications of these findings are discussed.

Adolescent↗