Early detection of autism spectrum disorders (ASD) is a prerequisite for early intervention. Questionnaires may offer a cost-effective alternative to clinician-led screening in identifying toddlers and preschoolers in primary-care settings requiring specialized ASD assessment. Parents of 97 children aged 16-60 months attending childcare centers were recruited. Parents completed the 10-item Parents' Evaluations of Developmental Status (PEDS) and an ASD screening questionnaire--the 23-item Modified Checklist for Autism in Toddlers (M-CHAT). Five percent of children required specialized ASD assessment based on their M-CHAT scores. Using a PEDS total score cutoff of 4 or more, these children were detected with an adjusted rate of 65% sensitivity and 88% specificity. These data provide some support for tiered screening with the PEDS and M-CHAT in identifying children requiring specialized ASD assessment. Given PEDS is a universally administered developmental screen in many jurisdictions, further research using PEDS and M-CHAT is warranted.