Thus, a better understanding of the latent structure of the disorder has obvious clinical implications. Furthermore, it is an important issue for research given that most studies use a dimensional approach to symptom measurement (Frick and Nigg, 2012) despite the categorical treatment of ODD in the DSM-5 (APA, 2013) and its predecessor the DSM-IV-TR (APA, 2000), the latter of which did not even include an ODD severity index (Pardini et al., 2013). As such, evidence for a dimensional latent structure of ODD would bolster the decision to treat measurement of the construct on a continuum. Likewise, use of a categorical classification (particularly a dichotomy, such as having a diagnosis or not) for a naturally dimensional construct, would minimize the predictive validity of measures assessing that construct when they are used to form categories (cf. Fergusson et al., 2010). Thus, evidence of a dimensional latent structure of ODD would contraindicate the dichotomization of otherwise continuous measures for the purposes of forming groups (i.e., with and without ODD) in research.
