There is evidence that cultural background influences the expression, interpretation and value given to psychiatric symptoms [
18]. An important goal of both the Diagnostic Statistical Manual, Fourth Edition (DSM-IV) American Psychiatric Association [APA] [
3] and the International Statistical Classification of Diseases and Related Health Problems, 10
th edition (ICD-10) (WHO [
83]) is to provide descriptions of valid diagnostic constructs that can be applied across age, gender, ethnicities and cultures or contexts [
63]. Consistent with this goal, the DSM-IV included a section on Specific Culture, Age and Gender Features for each diagnostic category which is intended to guide the clinician on variations of the disorder that may be attributable to the individual’s culture, sex or developmental stage. However, how well this goal has been achieved by this approach is a matter of controversy. In this paper, we are especially interested in the extent to which diagnostic criteria for conduct disorder (CD) and oppositional defiant disorder (ODD) are valid across cultures.
According to DSM-IV, all diagnoses should be applied only if the symptoms are the result of an underlying dysfunction within the individual and not a reaction to the immediate social context or a problematic environment. This inclusion represents a genuine attempt of DSM-IV to include contextual factors into the definition of disorders. Nevertheless, and as stated elsewhere [
17], the DSM-IV has not formally incorporated social or cultural factors as exclusionary criteria of disorders, nor are explicit definitions of underlying dysfunctions provided for each disorder. As a result, it is difficult and sometimes impossible to distinguish between behaviors caused by negative environments that do not involve internal dysfunction and those that originate from negative environments but do involve internal dysfunction [
80]. Some have questioned whether this distinction is appropriate and even possible (see [
54]). However, it is clear that most clinicians and research using epidemiologic surveys are not able to distinguish between symptoms that cause an internal dysfunction from those that are merely reflections of a negative environment [
11]. Moreover, research has demonstrated that negative environments can be influenced by a child’s genetic make-up and that genes can influence a child’s susceptibility to environmental stressors in the development of CD [
50,
69] making it extremely difficult to disentangle environmental and genetic influences.
Children from ethnic minorities and /or living in developing poor countries have a greater risk of exposure to deprived or negative environments than non-minority or children living in developed countries. Ethnic minorities in the US, as well as children in poor countries have higher exposure to poor prenatal care and poor infant nutrition, more exposure to toxic and infection agents, live in disadvantaged and crime ridden neighborhoods and are often exposed to other stressful circumstances associated with physical abuse and poverty. All of these are risk factors that have been associated with CD and ODD (See [
15,
55] for reviews). On the other hand, there is evidence that protective factors related to positive family environment may lower the prevalence of disruptive disorders even in developing or poor countries. For example, results of a longitudinal study of CD and ODD which compared the risk and protective factors of these disorders among Puerto Rican children living in San Juan, Puerto Rico and the Bronx showed that close family attachments and strict family monitoring and supervision [
12] typical of the Puerto Rican culture were associated with lower prevalence of CD and ODD. Both risk and protective factors associated with CD and ODD are often highly correlated, and studies have not consistently disentangled whether the low or high prevalence rates of CD and ODD in poor or minority samples are due to differences in poverty or neighborhood characteristics or other risk factors, rather than to cultural differences that may be associated with protective factors [
37].
Prevalence rates can also be affected by cultural factors related to the degree to which CD and ODD symptoms are considered dysfunctional and or are differentially tolerated in various cultures and across age groups. For example, suppression of aggression, anger and strong emotions or overt behaviors is part of the Chinese culture as well as the Thai culture. This cultural suppression may lead parents to have a lower threshold (or tolerance) for externalizing behaviors and to curb this behavior more often than in other cultures where these behaviors are more accepted. In fact, studies of case vignettes comparing Thai and American parents showed very different thresholds for internalizing versus externalizing behaviors with Thai parents more concerned about internalizing, over-controlled behavior than American parents [
81]. Given these cross cultural differences in parental perceptions and expectations of children’s behaviors, it is not surprising that comparisons of children’s syndromes across 16 different regions of the world as ascertained by the Child Behavior Checklist (CBCL) showed higher prevalence rates of internalizing syndromes and lower rates of externalizing syndromes in the Asian countries as compared to several Western countries [
27]. In fact, a longitudinal 25 year follow up of a community sample of children from the United Kingdom (from 1970’s to the late 1990s), showed that conduct problems significantly increased over this time period for children of both sexes and all socio-economic classes [
22]. The long term outcomes for adolescents with conduct problems were similar across time providing evidence that the observed trends were not due to changing report effects. More recently, a five year follow up of this same cohort was performed [
23]. The results showed that conduct problems as reported by parent, youth, and teachers either remained stable or slightly declined. Nevertheless, the extent to which these findings generalize to specific externalizing disorders such as CD and ODD need to be determined.
With this preamble in mind, in this paper, we review the literature on prevalence rates of DSM-III-R and DSM-IV CD and ODD across cultures, age, and ethnicities as evidenced by epidemiologic studies carried out in probability community or school samples. We excluded from our review findings treatment samples since they can be biased due to selection effects [
20]. Bias can arise because clinical studies tend to focus on persons with more chronic and severe manifestations of the disorder. If selection bias is ignored, the estimates of prevalence, patterns of correlates, co-morbidity and impairment can be affected by statistical bias known as Berkson’s bias [
5,
9].
Our aim is to present the first of four criteria previously described for determining the validity of psychiatric disorders across cultures [
10,
67]. The lack of established biological and genetic markers that are specific and replicated across samples [
45], imprecise measurement, and lack of a gold standard for validating most psychiatric conditions makes these criteria relevant for reaching an approximation of the validity of psychiatric disorders. The first of these criteria states that the syndrome or disorder should be described similarly across cultures. This can be accomplished by either anecdotal reports of mental health professionals or the collective clinical wisdom of these professionals in a given setting or by the systematic gathering and analyses of epidemiologic data [
10]. Remaining criteria are related to differentiation or delimitation from other disorders, the commonality in clinical outcomes and differential treatment response, diagnostic consistency over time, differentiation of risk factors, genetic aggregation in families, and differentiation of disorders by laboratory studies (e.g., functional imaging) and will not be addressed in this paper [
45,
67].
In this paper we examine the first cross cultural validity criterion using literature reviews to determine the extent to which the prevalence rates of CD and ODD vary across cultures as ascertained in population or school based samples. We exclude from our review the few studies which used solely the ICD-10 classification of psychiatric disorders in order to reduce variability across studies that could be due to case definition. Also, the main purpose of the paper is to inform the future DSM-V psychiatric classification. We also examine the prevalence rates of CD and ODD across cultures or ethnicities and use meta -regression analyzes to determine the methodological and cross cultural factors associated with the heterogeneity of the prevalence estimates. Prior research has found that prevalence estimates of most children psychiatric disorders as assessed in population-based studies vary dramatically depending on the measure or diagnostic criteria [
24,
55]. For example, concerns about the high rates of false positives in many population-based studies using DSM-III and DSM-III-R led to the addition of a clinical significance criterion for most specific disorders of DSM-IV that required a greater emphasis on clinical distress or impairment for case definition. As a result of the introduction of this criterion, most population- based epidemiologic studies that used the DSM-IV criteria observed much lower rates of psychiatric disorder than previously obtained in prior DSM-III-R studies (ranging from 17 to 20%) [
12,
19,
34,
35,
41]. Prevalence rates of child psychiatric disorders also vary depending on the type of informant ascertained (i.e. parent, child or teacher) [
42], the age of the child [
11,
14], how data provided by different informants (i.e. parent, teacher or child) are combined [
48] and whether or not impairment is used in the definition of a case [
19,
71].
To our knowledge this is the first study to present data on the world-wide prevalence of CD and ODD as a first step in evaluating the validity of these disorders in different cultures. Several other studies have reviewed the literature and presented rates of overall psychopathology in children across cultures [
11,
14,
24,
66] but have not presented data on specific psychiatric disorders such as CD and ODD. Nevertheless, a recent study presented data on the prevalence rates of ADHD across cultures and showed that variability across studies regarding diagnostic criteria, source of information (whether parent, child or teacher), and requirement of impairment for diagnosis, accounted mostly for differences in prevalence rates [
64]. No geographical difference between North America and Europe was observed. Given these previous results, we expect significant variability mainly related to methodological factors, in the prevalence of CD and ODD across cultures and ethnicity. However, we also expect significant heterogeneity in prevalence rates due to geographic or cultural variability, given the importance of contextual and environmental factors associated with ODD and CD.