Spanish-speaking families with a child 9 to 60 months of age (N = 991) were initially screened using Spanish translations of the SWYC Milestones and the ASQ-3. A stratified random sample of 494 of these children subsequently received standardized clinical assessment to confirm the presence of developmental delays. Reverse weighting corrected for the selection bias inherent in the stratification scheme.
Fifty-five percent of toddlers (9 to 41 months of age) and 34.8% of preschoolers (42 to 60 months of age) scored in the moderately to severely delayed range, most frequently in language. Sensitivity and specificity for toddlers with severe delays associated with the SWYC were 0.69 and 0.64, respectively, and 0.55 and 0.75 for the ASQ-3. Sensitivity and specificity for preschoolers with severe delays associated with the SWYC were 0.87 and 0.58, respectively, and 0.71 and 0.86 for the ASQ-3.
Although psychometric properties of the Spanish translated versions are not as strong as the English versions, the findings suggest that both the SWYC Milestones and ASQ-3 represent promising tools for identifying Hispanic children with developmental delays. The rate of delays were consistent with other studies showing a high percentage of Hispanic children with developmental delays, most frequently in language skills.