Early mobilization in pediatric intensive care units (PICUs) is essential to minimize complications and promote functional recovery. However, there is a lack of validated tools specifically designed to assess mobility in children with critical illness. The Perme ICU Mobility Score (Perme Score), originally developed for adults, assesses mobility considering barriers such as medical devices and ventilatory support. The validation of the Perme Score for pediatric use is crucial to guide rehabilitation strategies in this population.

To validate the Perme Score for evaluating mobility in patients admitted to PICU and pediatric wards, by analyzing its inter-rater reliability and its correlation with the Functional Status Scale (FSS), a widely used instrument in the pediatric population.

A cross-sectional observational study was conducted in two hospitals including pediatric patients aged 6 to 17 years. The Perme Score and FSS were applied independently by trained physical therapists. Inter-rater reliability was assessed using the intraclass correlation coefficient (ICC), while the correlation between the two tools was analyzed using Pearson&apos;s test. P-value < 0.05 was defined statistically significant.

A total of 166 participants were included, with a median age of 11 years. The initial assessment showed a mean Perme Score of 26.13±7.89 and a mean FSS of 7.25±2.21. A moderate to strong negative correlation was observed between the Perme Score and FSS (r = -0.642; p < 0.01), indicating that better mobility is associated with less functional impairment. Interrater reliability was excellent (ICC = 0.99).

The Perme Score proved to be a valid and reliable tool for assessing mobility in hospitalized pediatric patients. Its structured approach allows for the identification of mobility barriers and effective monitoring of functional progress throughout hospitalization.

Validating the Perme Score for the pediatric population supports its integration into clinical practice in both ICU and ward settings. The Perme Score can support early mobilization protocols and contribute to personalized rehabilitation strategies by objectively assessing mobility status of patients. Consequently, it has the potential to improve functional outcomes for critically ill children and promote evidence-based decision-making in physical therapy.