Chelsea critical care physical assessment tool (CPAx) for adult patients hospitalized in the ward: measurement properties

Objective To evaluate the measurement properties of the Brazilian version of the Chelsea Critical Care Physical Assessment Tool (CPAx-Br) and evaluate the evidence of validity in adult general ward patients, extending its application beyond the critical care setting for which it was originally developed. Methods This longitudinal study included 100 adults (57.5 ± 16.7 years; 54% female) consecutively admitted to hospital wards. The CPAx-Br was applied at three time points: within 48 h of admission, alongside the De Morton Mobility Index (DEMMI) and the Global Rating Scale of Change (GRC); 24 h later to assess reliability; and at hospital discharge, again with the DEMMI and GRC. As part of construct validity, hypothesis testing was performed using Spearman's correlation with the DEMMI. Reliability was tested using the Intraclass Correlation Coefficient (ICC 2,1 ) and Standard Error of Measurement (SEM). Responsiveness was evaluated using ROC curve analysis, effect size (ES), and correlation with external measures. Floor and ceiling effects were also examined. Results The CPAx-Br demonstrated adequate reliability (ICC 2,1 = 0.99; 95%CI:0.99–1.00) and measurement error (SEM=0.985). Evidence supporting construct validity was obtained through hypothesis testing, demonstrating a positive correlation with the DEMMI (r = 0.895; p < 0.001). Internal responsiveness was low (ES=0.35), while external met the predefined criterion (r = 0.70; p < 0.001). The CPAx-Br showed acceptable discriminative ability (AUC=0.70; 95% CI 0.54 to 0.85), with no floor effect (0%), whereas the ceiling effect was 16%. Conclusion The CPAx-Br demonstrated validity based on hypothesis testing, as well as good reliability and acceptable responsiveness for assessing physical function among adult ward patients.