The findings of this article provide the first estimates of the prevalence of DSM-IV–defined mental disorders in a broad age range of children in the general population of the United States. The most-common 12-month disorder was ADHD (8.7%),17
followed by mood disorders (3.7%), conduct disorder (2.1%),18
and panic disorder/GAD (0.7%). Eating disorders were very rare (0.1%). With the exception of ADHD, these rates are substantially lower than those reported in other prevalence studies of mental disorders in children.21–23
However, they are quite comparable to findings from other US studies that used similar diagnostic methods and criteria24–28
and are strikingly similar to those reported for a community survey conducted at the same time in Houston, Texas.26
The sociodemographic correlates of mental disorders in this survey also confirmed those of previous community studies of youths in the United States.25–35
The prevalence of mood disorders was greater in girls, whereas there was a male preponderance of ADHD. Inspection of age-specific prevalence rates revealed that the rates of mood disorders were higher among older children, compared with younger children, whereas the rates of conduct disorder were higher among early adolescents (12–15 years of age), compared with younger children. In general, there were few ethnic differences in disorders studied in this survey; however, Mexican American youths had significantly higher rates of mood disorders than did either white or black youths. Finally, poor children had higher rates of any disorder and ADHD and lower rates of anxiety disorders than did their wealthier counterparts.
Comorbidity was less common among youths in this survey than in comparable studies of adults, where the majority of studies found that few individuals in the population had only 1 disorder. In the present study, only 1.8% (SE: 0.3%) of youths 8 to 15 years of age had >1 disorder. Similar to previous community studies,21
the disorders with the highest rates of cooccurrence were conduct disorder and ADHD. Previous prevalence studies of children and adolescents yielded far higher rates of comorbidity, particularly those that assessed lifetime disorders.21,30,36,37
The lower rates of comorbidity are likely attributable to the limited number of disorders assessed in the current study, compared with the full range of disorders assessed in other studies.
With respect to service use, we found that about one half of those who had 1 of the mental disorders examined in this survey during the past year had sought treatment in the mental health sector. Approximately one half of those with ADHD had sought mental health treatment. This finding confirms the continuing increase in service use for childhood mental disorders, particularly ADHD, in recent decades.38–42
Nearly equal proportions of those with conduct disorder (46.4%) and mood disorders (43.8%) reported service contacts for those conditions.43
There was a moderate range of treatment rates for specific subtypes of disorders, ranging from 47.7% mental health service use among those with ADHD to 32.2% among those with GAD or panic disorder. Treatment rates increased substantially for those with panic disorder/GAD, eating disorders, and/or mood disorders when the sample was restricted to youths with severe impairment. Despite the relatively large proportions of youths with ADHD, conduct disorder, and mood disorders who sought mental health services specifically for those disorders, only a minority (32.2%) of youths with anxiety disorders, even those with severe impairment, did so. This confirms the consistent finding from previous studies that up to 80% of youths with anxiety disorders do not use health services.44
Increased education about the availability of effective treatments for anxiety disorders are also may be warranted.
This study has several strengths. It provides the first estimates of the prevalence of specific DSM-IV–defined mental disorders in the US population of children and adolescents. The reliability of the prevalence rates is enhanced by the use of repeated surveys over 4 years, which increases the precision of the estimates. The use of a structured interview and standardized diagnostic criteria facilitate comparisons of these findings with those of other local studies in the United States and in international settings. Information that supplements the diagnostic data in this study includes ratings of the clinical significance of the disorders through inclusion of systematic information on different levels of functional impairment; data on service-seeking for specific disorders, as well as for mental health services in general; and a comprehensive series of laboratory measurements and assessments of numerous physical disorders and health behaviors. Future reports on this survey will address these potential correlates of mental health.
There are several methodologic features of this study that should be considered as possible sources of differences from the findings of previous studies. First, it is likely that these findings are underestimates of the true population base rates, because the most-common disorders in children, including separation anxiety and phobic states, were not included in the survey.21,45
Second, the rates of most disorders in this study were based on reports of only 1 informant, rather than information from both parent and child informants, which has been shown to provide the most-valid information on disorders in youths.46
Third, the parent report was obtained by telephone after completion of the direct assessment of the child. This would be expected to yield different rates, compared with studies that assess both informants in the same direct interview.
The rates are based solely on reports of the diagnostic criteria by either the parent or the child, rather than clinicians or teachers, who may be more knowledgeable about impairment and disability either in the individual youths or among comparable children as a frame of reference. Fourth, there were no systematic clinical evaluations to validate the diagnoses.16,47,48
The generally low base rates of most disorders in this study should be interpreted in the context of the methods used in this study. Reviews of the aggregate data from population-based studies have shown that different methods of ascertaining data on diagnostic criteria (eg, symptom rating scales, structured and semistructured diagnostic interviews, and objective measures) can yield a wide range of prevalence estimates.11,21
It will be important to consider a range of prevalence estimates, depending on the specific goals of the application of morbidity rates. Nevertheless, the similarity between our findings and those of previous community surveys that generated 12-month estimates of mental disorders in children on the basis of DISC and DSM-IV criteria demonstrated the reliability of the methods used here. The large variation between our estimates and those of studies using other diagnostic interviews, prevalence periods, and constellations of disorders also highlights the need for research designed to validate the diagnostic classification of mental disorders in children.7–9,11,21,49–51
This study has begun to address the gap in knowledge regarding national patterns of mental health problems in children. When combined with the results of several regional epidemiological studies of mental disorders in children11
and other national, population-based studies now underway (including the National Comorbidity Survey Adolescent Supplement,52,53
), these data will provide a valuable empirical basis for the development of health policies designed to maximize prevention efforts and to minimize the consequences of these conditions in US youths.
WHAT’S KNOWN ON THIS SUBJECT
Although there have been several regional community surveys of mental disorders in the United States, there are no studies of DSM-IV–defined disorders in a representative sample of US youths.
WHAT THIS STUDY ADDS
This study adds new information about the prevalence of DSM-IV–defined mental disorders and service patterns in a general population sample in the United States.