• instrument development;
  • nursing care intensity;
  • patient classification;
  • reliability;
  • validity;
  • workload measurement



This paper assessed the reliability and construct validity of the new version of a patient classification instrument.


In the development of patient classification instruments, monitoring validity and reliability is essential to assure that patient care requirements and nursing staff workload are appropriately measured.

Design method

The sample included 194 patients (construct validity test) and 60 patients (inter-rater reliability test) at medical, surgical, and specialized wards of a teaching hospital in the south east of Brazil. The study was conducted in 2009–2010. For analysis purposes, Spearman's correlation and Cronbach's alpha (internal consistency) were used, and weighted kappa (inter-rater reliability), factor analysis with principal axis factoring extraction method (construct validity) and ordinal regression (instrument's predictive ability).


A high level of inter-rater agreement was found. The importance of all care areas and their contribution to distinguish patient care needs and category in the new instrument were demonstrated. Results also showed the instrument's high predictive ability (99·6%).


The findings give the evidence that the new scale is a reliable and valid tool to assess patient care needs and care category and that it can be used to guide nursing management practice in determining the nursing staff workload.