Fig. 2.

Multidimensional models for analyzing multi-faceted constructs. (a) Multidimensional model with correlated first-order facet-specific factors for hyperactivity-impulsivity (HI), inattention (IN), and oppositional defiant disorder (OD). (b) Bifactor S-1 model presented by Burns et al. (this issue) with hyperactivity-impulsivity (HI) as general reference factor (GRF-HI) and two specific reference factors for inattention (SRF-IN) and oppositional defiant disorder (SRF-OD). (c) Bifactor S-1 model with a directly assessed general hyperactivity-impulsivity factor (GF-HI) and three specific reference factors for hyperactivity-impulsivity assessed in specific situations (SRF-HI1, SRF-HI2, SRF-HI3). Y_ij: observed variables, E_ij: error variables, λ_ij: factor loadings, i: indicator, j: facet