title: Initial description of a quantitative, cross-species (chimpanzee-human) social responsiveness measure.
abstract: OBJECTIVE
  Comparative studies of social responsiveness, an ability that is impaired in autism spectrum disorders, can inform our understanding of both autism and the cognitive architecture of social behavior. Because there is no existing quantitative measure of social responsiveness in chimpanzees, we generated a quantitative, cross-species (human-chimpanzee) social responsiveness measure.
  
  
  METHODS
  We translated the Social Responsiveness Scale (SRS), an instrument that quantifies human social responsiveness, into an analogous instrument for chimpanzees. We then retranslated this "Chimpanzee SRS" into a human "Cross-Species SRS" (XSRS). We evaluated three groups of chimpanzees (n = 29) with the Chimpanzee SRS and typical and human children with autism spectrum disorder (ASD; n = 20) with the XSRS.
  
  
  RESULTS
  The Chimpanzee SRS demonstrated strong interrater reliability at the three sites (ranges for individual ICCs: 0.534 to 0.866; mean ICCs: 0.851 to 0.970). As has been observed in human beings, exploratory principal components analysis of Chimpanzee SRS scores supports a single factor underlying chimpanzee social responsiveness. Human subjects' XSRS scores were fully concordant with their SRS scores (r = 0.976, p = .001) and distinguished appropriately between typical and ASD subjects. One chimpanzee known for inappropriate social behavior displayed a significantly higher score than all other chimpanzees at its site, demonstrating the scale's ability to detect impaired social responsiveness in chimpanzees.
  
  
  CONCLUSIONS
  Our initial cross-species social responsiveness scale proved reliable and discriminated differences in social responsiveness across (in a relative sense) and within (in a more objectively quantifiable manner) human beings and chimpanzees.
authors.affiliation: Washington University School of Medicine, USA. marrusn@psychiatry.wustl.edu
authors.forename: Natasha
authors.initials: N
authors.lastname: Marrus
authors.forename: Carley
authors.initials: C
authors.lastname: Faughn
authors.forename: Jeremy
authors.initials: J
authors.lastname: Shuman
authors.forename: Steve E
authors.initials: SE
authors.lastname: Petersen
authors.forename: John N
authors.initials: JN
authors.lastname: Constantino
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Povinelli
authors.forename: John R
authors.initials: JR
authors.lastname: Pruett
mesh_terms: D000818:Animals; D002648:Child; D002659:Child Development Disorders, Pervasive / Q000175:diagnosis* / Q000523:psychology*; D004195:Disease Models, Animal; D005260:Female; D006801:Humans; D008297:Male; D015588:Observer Variation; D002679:Pan troglodytes / Q000523:psychology*; D010552:Personality Assessment / Q000706:statistics & numerical data*; D011594:Psychometrics / Q000706:statistics & numerical data; D012016:Reference Values; D015203:Reproducibility of Results; D012919:Social Behavior; D013045:Species Specificity