Results of this study suggested that it is a specific group of externalized behaviours that are the most strongly associated with both parent and teacher stress. Results were discussed from methodological and conceptual perspectives.

Background In addition to the core symptoms, children with Pervasive Developmental Disorders (PDD) often exhibit other problem behaviors such as aggression, hyperactivity, and anxiety, which can contribute to overall impairment and, therefore, become the focus of clinical attention. Limited data are available on the prevalence of anxiety in these children. We examined frequency and correlates of parent-rated anxiety symptoms in a large sample of children with PDD. Methods The goals of this study were to examine the frequency and correlates of parent-rated anxiety symptoms in a sample of 171 medication-free children with PDD who participated in two NIH-funded medication trials. Twenty items of the Child and Adolescent Symptom Inventory (CASI) were used to measure anxiety. Results Forty three percent of the total sample met screening cut-off criteria for at least one anxiety disorder. Higher levels of anxiety on the 20-item CASI scale were associated with higher IQ, the presence of functional language use, and with higher levels of stereotyped behaviors. In children with higher IQ, anxiety was also associated with greater impairment in social reciprocity. Conclusion Anxiety is common in PDD and warrants consideration in clinical evaluation and treatment planning. This study suggests that parent ratings could be a useful source of information about anxiety symptoms in this population. Some

Parents or teachers rated 487 non-clinically referred young people with Pervasive Developmental Disorders on the Nisonger Child Behavior Rating Form. The objectives of the study were to examine the relative prevalence of specific behavior problems, assess the impact of subject characteristics, and derive an empirical classification of behavioral and emotional problems for this population. Results indicated that the youngsters experienced high rates of behavior and emotional problems. Cluster analysis suggested that six- and eight-cluster solutions best fit the ratings provided by parents and teachers, respectively. Both parent and teacher cluster solutions contained groups of children characterized as problem free, well adapted, hyperactive, anxious, and with undifferentiated behavior disturbances. The empirically derived clusters were supported by data external to the analyses.

IMPORTANCE Disruptive behavior is common in children with autism spectrum disorder. Behavioral interventions are used to treat disruptive behavior but have not been evaluated in large-scale randomized trials. OBJECTIVE To evaluate the efficacy of parent training for children with autism spectrum disorder and disruptive behavior. DESIGN, SETTING, AND PARTICIPANTS This 24-week randomized trial compared parent training (n = 89) to parent education (n = 91

Exploratory factor analysis (EFA) is a widely used but poorly understood statistical procedure. This paper described EFA and its methodological variations. Then, key methodological variations were used to evaluate EFA usage over a 10-year period in five leading developmental disabilities journals. Sixty-six studies were located and evaluated on multiple procedural variations. Only 35% (n = 23) of studies used EFA; principal components analysis was the model used most often (n = 40, 61%). Orthogonal rotation was used most often (n = 39, 59%). A large portion of studies ran analyses with a subject: item ratio larger than 5:1 (n = 49, 74%). Most researchers employed multiple criteria for retaining factors (n = 45, 68%). Overall, results indicated that published recommendations and guidelines for the use of EFA are largely ignored.