Investigating the Measurement Invariance and Method-Trait Effects of Parent and Teacher SNAP-IV Ratings of Preschool Children.

The Swanson, Nolan, and Pelham scale version IV (SNAP-IV) is widely used to assess symptoms of attention deficit hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD) in children and adolescents. Nevertheless, there is insufficient data to support its use in preschool children. The study had three goals: First, to test the factorial validity of the three correlated-factors model of ADHD and ODD items of the SNAP-IV. Second, to investigate the measurement invariance of the items over time (6-month longitudinal interval) and by sex. Third, to investigate the convergent validity and method-specific influences on ADHD/ODD assessments with respect to multiple raters (parents/teachers) of children's symptoms. Participants were 618 preschool children (3.5-6 years) at baseline and 6-month follow-up. For model testing, we used confirmatory factor analysis for categorical observed variables. Method and trait effects were examined using the CT-C(M-1) model. The analyses showed partial measurement invariance over time and according to sex. Moreover, strong rater-specific effects were detected. The implication of the results for construct validation of the instrument and clinical assessment of ADHD and ODD traits are discussed.

Evaluating Parental Disagreement in ADHD Diagnosis: Can We Rely on a Single Report From Home?

OBJECTIVE: Few studies assessed factors associated with the agreement/disagreement between fathers and mothers when rating ADHD symptoms of their offspring. METHOD: Teachers and both parents assessed a referred sample of 98 children and adolescents aged 6 to 16 years ( M age = 9.79, SD = 2.59) using the Swanson, Nolan, and Pelham (SNAP-IV) rating scale. The agreement was assessed for each of the items of the scale and correlated with variables measuring children's features, socioeconomic adversity, family functioning, and parental psychopathology. RESULTS: Mean agreement between parents was moderate for the inattentive and good for the hyperactive-impulsive construct. Mothers tended to report more symptoms than fathers. The agreement was lower in those families where parents had discrepant educational levels. CONCLUSION: Our findings suggest a significant cross-informant disagreement between parents on symptoms of ADHD. Discrepant parental education has a relevant role in explaining parental disagreement in reporting ADHD symptoms.