• Nursing Work Index;
  • NWI;
  • NWI-R;
  • nursing practice environment;
  • nursing practice environment index;
  • PEI;
  • psychometrics;
  • hospital outcomes;
  • factor analysis


The primary purpose of this study is to document the psychometric properties of the revised Nursing Work Index (NWI-R) in the context of a large Canadian sample of registered nurses. A self-administered survey containing the NWI-R was completed by 17,965 registered nurses working in 415 hospitals in three Canadian provinces. Using exploratory principal components analysis, with a forced one-factor solution, the practice environment index was obtained. In addition, key assumptions were tested from previous work about the rationale for the aggregation of NWI-R responses. In the Canadian context the one-factor solution provides a parsimonious index of the practice environment of registered nurses working in acute care hospitals. Further work is needed to determine the predictive capability of this index and its relevance to cross-national organizational contexts. © 2002 Wiley Periodicals, Inc. Res Nurs Health 25:256–268, 2002