RESUMEN
The Infant Toddler Activity Card Sort (ITACS) is a new measure that engages caregivers in goal development by measuring participation in early childhood. Initial evaluation of the ITACS is required to assess its psychometric properties. To evaluate test-retest reliability, concurrent validity, and between-group differences of the ITACS. Caregivers (N = 208) of children 0-3 years, who were typically developing (TD) or had a developmental delay (DD), completed the ITACS and Pediatric Evaluation of Disability Inventory-Computer Adaptive Test (PEDI-CAT) with repeat assessment after 2 weeks later (n = 117). The ITACS demonstrated moderate concurrent validity with the PEDI-CAT. Children with DD had significantly more activity concerns on the ITACS than TD. Adequate test-retest reliability was not achieved. The ITACS is a useful tool for identifying caregiver concerns in activity engagement; interventions can be tailored to address concerns and increase participation in childhood routines.