Evidence suggests that oppositional defiant disorder (ODD) and conduct disorder (CD) are closely related in taxonomic and developmental terms [1]. Although ODD and CD are considered as two independent disorders, the behaviors that define ODD have long been hypothesized to be developmental precursors to serious conduct problems [2–4]. However, not all children with ODD will necessarily progress to CD [6–12] suggesting some discontinuity between the disorders. Determining whether ODD is a risk factor for, or develops secondarily to CD is of particular theoretical and clinical importance as it could suggest different etiological models and intervention efforts.

First, significant temporal associations between the two constructs are more likely in clinical- than in community-based samples [6, 8]. However, because clinical samples are typically subject to higher rates of comorbidity, studies of clinical samples may have exaggerated the degree of the temporal relations between ODD and CD [13]. Second, in the DSM [14] CD and ODD are not allowed to be comorbid diagnoses. As a result, the use of clinical cut-offs in assigning ODD and CD diagnoses in studies may have boosted the prediction of CD from previous levels of ODD when subclinical levels of CD have not been considered, whereas the appearance of more ‘severe’ manifestations of CD may have overshadowed the stability of ODD. Only two studies in Table 1 utilized a dimensional approach assessing the two constructs as a continuum to avoid over- or underestimating their temporal relations and reached strikingly different conclusions: ODD is [2] and ODD is not [10] a precursor of CD. Perhaps, the discrepant findings of the two above studies are due to the use of different ODD measures (i.e., DSM-III-R ODD diagnosis based on clinic interviews in the study by Burke et al.; retrospective DSM-IV ODD diagnosis based on parent and teacher questionnaires in the study by Mannuzza et al.). Third, as two literature reviews suggest that ODD is more likely to be a precursor of CD in early (i.e., up to the age of 7 years) than in late childhood [1, 15], age effects may explain the studies’ discrepant findings. For instance, two studies in Table 1 that measured ODD in early childhood [3, 9] reported significant prospective associations between ODD and CD, whereas two studies that measured ODD after the age of six reported weak or no prospective associations between ODD and CD [4, 6]. Finally, discrepancies between the findings in the literature may also be due to the use of different conceptualizations of ODD and CD including diagnoses according to older versions of the DSM [10, 12], diagnoses based on parental questionnaires [6, 9] versus diagnostic interviews [2, 5]. Clearly, more research on the temporal relations between ODD and CD assessing the two constructs dimensionally from early childhood to adolescence is needed.

Certain limitations in the literature need also to be overcome if we are to understand the relations between ODD and CD across time. First, because of the higher prevalence of ODD and CD in boys as compared to girls [16, 17], little is known about the development of the two constructs in girls. Interestingly, the one study that examined gender differences in the prospective associations between ODD and CD showed that ODD appears to be a developmental precursor to CD only among boys [11]. Second, because symptoms of attention deficit hyperactivity disorder (ADHD) often co-occur with both ODD and CD and may even partly account for the developmental progression of ODD into CD [18] studies need to control for ADHD symptoms when examining the developmental relations between ODD and CD.

This study aimed to overcome the above limitations in the literature and disentangle the developmental relations between ODD and CD symptoms from early childhood to adolescence assessing the two constructs dimensionally in a community-based sample.

Because the most parsimonious, correlation model fitted the data equally well as the cross-lagged- and the univariate model, we selected it as the final model. The standardized estimates for the correlational model are depicted in Fig. 2. Considering time intervals of 2 years for the five assessments, temporal stabilities for ODD, CD, and ADHD symptoms were high. The concurrent associations between ODD and CD symptoms were high across time and so were the associations between ADHD symptoms and the two constructs.

Fig. 2 Final correlational model. Note: All paths significant at p < 0.01 level

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To further examine the influence of ADHD symptoms on the temporal relations between ODD and CD symptoms, we examined the cross-lagged, unidirectional, and correlational models without control for ADHD symptoms. These three models also fitted the data well: CFI = 0.99 for all three models and RMSEA = 0.02 for the cross-lagged and the unidirectional models and RMSEA = 0.03 for the correlational model. Comparison of the models indicated that although the model fit of the cross-lagged versus the unidirectional model did not differ significantly (∆χ² [4] = 6.09, ns), the cross-lagged and the unidirectional models fitted the data better than the correlational model (∆χ² [8] = 19.21, p < 0.05 and ∆χ² [4] = 14.22, p < 0.05, respectively). However, none of the cross-lagged or unidirectional paths reached statistical significance indicating that even without control for ADHD symptoms ODD symptoms did not significantly predict subsequent CD symptoms and ODD and CD symptoms were not reciprocally associated across time. Results of analyses conducted separately for boys and girls replicated the above findings for boys but for girls the three models fitted the data equally well.

This study examined whether ODD symptoms should be viewed as precursors of later developing CD, whether ODD and CD are likely to show reciprocal temporal associations across time, or finally, whether ODD and CD develop parallel to each other. In line with the findings of previous studies of community-based samples, no temporal associations between ODD and CD symptoms were observed [6, 8]. Instead, the strongest predictor of subsequent CD symptoms was initial CD symptoms. What this study adds to the literature is that we confirm these findings for a lengthy follow-up period spanning from early childhood to adolescence, for both genders, using multiple assessments.

Keeping in mind that causal interpretations of results of longitudinal path analyses should be avoided and results should be interpreted with caution, the present findings do not suggest that ODD symptoms are a milder, earlier manifestation of CD. Neither do the results suggest that ODD symptoms may develop secondarily to CD symptoms, as none of the paths between ODD and CD symptom levels in the unidirectional and the cross-lagged models were significant. The results are in line with the study by Lahey et al. [9] that also used CBCL items to predict conduct problems from ADHD and ODD symptoms in a community-based sample. It should, however, be noted that the high temporal stability of both ODD and CD symptoms renders reciprocal associations between the two constructs less probable insofar as the greater the stability of a construct, the less the chance of finding other variables that potentially explain its variance [33].

In contrast to the findings by Rowe et al. [11], which are also based on a community-based sample, the temporal relations between ODD and CD symptoms did not differ by gender in this study. One possible reason for this is that whereas Rowe et al. [11] based their results on analyses utilizing clinical cut-offs, we examined the temporal relations between ODD and CD dimensionally in a sample that overall did not display very high symptom levels. Consequently, the findings of this study indicate that as long as negativistic and defiant behaviors in childhood are mild to moderate and do not reach clinical levels, boys and girls are equally likely to either outgrow these problems or not develop more serious conduct problems. Future studies need to examine whether the above findings hold even after control for other comorbid psychopathology such as depression and anxiety that may have different relations with ODD and CD symptoms in boys and girls.

Some previous studies suggest that children with ODD and ADHD are more likely to develop CD than children with ODD only [18]. Consequently, removal of ADHD symptoms from the measurement model should render the unidirectional model as better fitting than the correlational model. Nevertheless, results did not suggest such an effect although the concurrent associations between ADHD symptoms and both ODD and CD symptoms were significantly positive across all time points. Hence, it appears that in community-based samples, the impact of ADHD symptoms on the temporal relations between ODD and CD is minimal.

This study is not without limitations. First, like most previous longitudinal studies that examined the prospective relations between oppositional-, inattentive/hyperactive behaviors and later conduct problems the present analyses were not based on measures that were a perfect match to the DSM-IV symptom-criteria. A recent, large (N = 476), multi-ethnic, clinical study of children and adolescents confirmed the construct and discriminant validity of the DSM-oriented scales showing that the scales corresponded well (area under the curve values ≥0.71) with related clinical diagnoses [34]. However, it should be noted that in this latter study, the DSM-oriented scales of the CBCL for ODD, CD, and ADHD did not show greater correspondence with corresponding clinical diagnoses than the CBCL empirically derived syndrome scales of aggressive behavior, rule-breaking behavior, and attention problems. Moreover, the present findings are quite consistent with the smaller set of studies that did use DSM-based measures in terms of the concurrent associations found between ODD, CD, and ADHD (e.g. 5, 7) suggesting that the findings of this study are relevant to DSM conceptualizations of these disorders. Nevertheless, because different results may have been obtained had we used DSM-based measures, future longitudinal studies using such measures would be very useful. Second, because of the use of parent ratings, results may not generalize to studies using teacher or self-ratings of ODD and CD symptoms. Finally, the reliability of the CD scale at the first two time points was relatively low. Inspection of the results of the CFAs, we conducted showed that this was primarily caused by low loadings of two CD scale items namely, “Truancy” and “Threatens people”. The results are not unexpected given that at the first two time points of the study participants were very young and therefore, highly unlikely to attempt to be absent from school or have fully developed the language and cognitive skills in order to seriously threaten others.

One of the strengths of this study is that the multiple assessments allowed for the examination of competing models in terms of their ability to explain the dynamic, temporal linkage between ODD and CD symptoms. In conclusion, the findings suggest that the best predictor of subsequent CD symptoms is initial CD symptoms. However, ODD symptoms appear to carry unique information not captured by CD symptoms and given also their stability across childhood and early adolescence they deserve to receive attention beyond the context of being precursors to other disruptive behavior disorders. A clinical implication of the findings is that ODD and CD do not represent the same underlying pathology and possibly require different treatment.