Background The first stage of diagnosing autism spectrum disorders usually involves population screening to detect children at risk. The aim of this study was to develop cut-off points and assess diagnostic properties for the Polish version of the Communication and Symbolic Behavior Scales-Developmental Profile – Infant-Toddler Checklist for the possibility of using this questionnaire in population screening.

Method The study was conducted among 602 children from the general population who had previously participated in the earlier phase of validation of the questionnaire for Polish conditions. The collected data were statistically processed to calculate the accuracy (i.e. sensitivity, specificity) of the questionnaire.

Results In individual age groups, the sensitivity of the questionnaire varies from 0.667 to 0.750, specificity from 0.854 to 0.939, positive predictive value from 0.261 to 0.4 and negative predictive value - from 0.979 to 0.981.

Conclusions These results indicate that the Polish version of the Communication and Symbolic Behavior Scales-Developmental Profile – Infant-Toddler Checklist can be used as an effective tool for ASD universal screening.

The authors have declared no competing interest.

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Approval from the Bioethics Committee of the Wroclaw Medical University was obtained to conduct the study (number KB ߝ 641/2020). All procedures were performed in accordance with the 1964 Helsinki Declaration and its later amendments.

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