Cross-Cultural Validity of the Social Communication Questionnaire for Adults with Intellectual Developmental Disorder.

Diagnosing Autism Spectrum Disorders (ASD) is important throughout the lifespan. The objective was to investigate the transcultural diagnostic validity of the Social Communication Questionnaire (SCQ) in a clinical sample of 451 adults with Intellectual Developmental Disorder (IDD) with and without ASD in Germany, the U.S.A. and Great Britain. Variables associated with higher SCQ sum-scores were higher levels of IDD, male gender, a diagnosis of ASD and the study site (Germany > U.S.A > G.B.). An ROC analysis revealed a cut-score of 13, which resulted in a sensitivity of 0.87 and a specificity of 0.58. It is recommended to adjust the cut-score according to level of IDD and gender. Further research is needed to align diagnostic assignment of ASD across different sites and countries.