Scahill, LawrenceMcDougle, Christopher J.Williams, Susan K.Dimitropoulos, AnastasiaAman, Michael G.McCracken, James T.Tierney, ElaineArnold, L. EugeneCronin, PegeenGrados, MarcoGhuman, JaswinderKoenig, KathleenLam, Kristen S. L.McGough, JamesJosey, David J.Ritz, LouiseSwiezy, Naomi B.Vitiello, Benedetto2016-10-122016-10-122014-01-010890-8567http://hdl.handle.net/10919/73206Objective: To examine the psychometric properties of the Children's Yale-Brown Obsessive Compulsive Scales (CYBOCS) modified for pervasive developmental disorders (PDDs). Method: Raters from five Research Units on Pediatric Psychopharmacology (RUPP) Autism Network were trained to reliability. The modified scale (CYBOCS-PDD), which contains only the five Compulsion severity items (range 0-20), was administered to 172 medication-free children (mean 8.2 &#177; 2.6 years) with POD (autistic disorder, <i>n</i> = 152; Asperger's disorder, <i>n</i> = 6; POD not otherwise specified, <i>n</i> = 14) participating in RUPP clinical trials. Reliability was assessed by intraclass correlation coefficient (ICC) and internal consistency by Cronbach's a coefficient. Correlations with ratings of repetitive behavior and disruptive behavior were examined for validity. Results: Eleven raters showed excellent reliability (ICC= 0.97). The mean CYBOCS score was 14.4 (&#177; 3.86) with excellent internal consistency (&#945; = .85). Correlations with other measures of repetitive behavior ranged from <i>r</i> = 0.11 to <i>r</i> = 0.28 and were similar to correlations with measures of irritability (<i>r</i> = 0.24) and hyperactivity (<i>r</i> = 0.25). Children with higher scores on the CYBOCS-PDD had higher levels of maladaptive behaviors and lower adaptive functioning. Conclusions: The five- item CYBOCS-PDD is reliable, distinct from other measures of repetitive behavior, and sensitive to change.1114-1123 (10) page(s)enIn CopyrightPsychology, DevelopmentalPediatricsPsychiatryPsychologyautismclinical measuresrepetitive behaviorPERVASIVE DEVELOPMENTAL DISORDERSRISPERIDONEArticle - Refereedhttps://doi.org/10.l097/0I.chi.0000220854.79l44.e7459