Dev Med Child Neurol. 2025 Aug 2. doi: 10.1111/dmcn.16415. Online ahead of print.ABSTRACTAIM: To investigate the validity of Selective Control Assessment of the Lower Extremity for Infants and Toddlers (Mini-SCALE), an adaptation of Selective Control Assessment of the Lower Extremity (SCALE), in young children aged from 3 months to less than 4 years.METHOD: Mini-SCALE was modified from SCALE and reviewed by 16 experienced clinicians to establish content validity. For convergent validity, Mini-SCALE was compared to the Developmental Assessment of Young Children, Second Edition, Gross Motor subdomain (DAYC-2 GM) for 50 participants (aged 4-46 months, 29 males) with cerebral palsy (CP) (n = 20), at risk for CP (n = 9), and typically developing participants (n = 21) using a prospective cross-sectional design. For known-group validity, the scores of children with or at risk for CP were compared to typically developing children using the Welch's two-sample t-test.RESULTS: Content validity was strong with 96.6% (range = 75%-100%) expert agreement on 54 statements about content, administration, and grading. Convergent validity was strong between Mini-SCALE and the DAYC-2 GM (Spearman's rank correlation coefficient, rs = 0.80; p < 0.001). Mini-SCALE discriminated between children with or at risk for CP and typically developing children (p < 0.001).INTERPRETATION: Mini-SCALE is a valid measure of selective motor control for young children with or at risk for CP.PMID:40751442 | DOI:10.1111/dmcn.16415