Nursing Activities Score (NAS): cross-cultural adaptation and validation to Portuguese language

Abstract

The study aimed to adapt to the Portuguese language and to evaluate the psychometric properties of the Nursing Activities Score (NAS), an instrument for measuring the nursing workload in ICUs. After the process of cross-cultural adaptation, the NAS was applied to a sample of 200 adult ICU patients. The analysis of internal consistency by Cronbach's alpha coefficient revealed that the NAS has 23 independent measures that do not allow for either consolidation or reduction. Assessment of inter-rater reliability showed high concordance level (99.8%) and a Kappa index average of 0.99. The concurrent validity was demonstrated by statistically significant correlation between the TISS-28 and NAS (r=0.67, p<0.0001), and by multivariate regression analysis (R²=94.4%, p<0.0001). The convergent validity was supported by the statistically significant association between the NAS and the SAPS II, when adjusted for age (R²=99.8%, p<0.0001). These results indicate that the NAS is a valid and reliable instrument to measure nursing workload of Brazilian ICUs.