The autism spectrum disorders (ASDs) can present with symptoms commonly found in mood and anxiety disorders. The Social Communication Questionnaire (SCQ), Children's Communication Checklist (CCC-2), and the Social Reciprocity Scale (SRS) were used to screen children in a mood disorders research clinic setting for symptoms of ASD. Ninety-three patients (mean age, 12.7 +/- 2.8 years; percent male, 63%) completed at least one scale, and 50 children completed all three. The prevalence of those screening positive for a possible ASD on one instrument was 62% and on all three measures was 8%. Fifty-seven percent (n = 21/37; odds ratio, 4.59 [95% confidence interval (CI) = 1.40-15.11]) of those scoring in the "ASD-likely" range on the SRS scored in that range on the CCC-2. Only 16% (n = 6/37; odds ratio, not significant (NS)) of those scoring in the ASD-likely range on the SRS, and 14% (n = 5/37; odds ratio, NS) of those scoring in the ASD-likely range on the CCC-2, scored similarly on the SCQ. These results demonstrate a need to develop valid and reliable instruments to screen for ASDs in children presenting outside of ASD clinics.