title: An exploration of the factor structure of the nursing work index.
abstract: BACKGROUND
  The nurse shortage is increasing in the developed world. Organisational context is important in determining issues associated with nurse shortages, such as retention, recruitment, and job satisfaction. Recent research has utilised the Nursing Work Index-Revised (NWI-R) as a measure of organisational context traits. Within the NWI-R a four-factor model has been reported as being important in determining good organisational context, yet researchers have recently questioned the stability of the four-factor structure.
  
  
  OBJECTIVE
  No known study has attempted to replicate the four-factor structure reported in the NWI-R. The aim of this research is to examine the factor structure of the 15 items that comprise the four factors of the NWI-R.
  
  
  METHODS
  The NWI-R is an instrument that is focused on capturing organisational attributes that characterise professional nursing environments. A random sample of 172 (50%) acute care hospital nurses completed the NWI-R as part of a larger research project. The sample was diverse concerning nursing grade and specialty. Data were analysed using SPSS.11.0 to extract factors' structures (principal component and maximum likelihood), measures of homogeneity and descriptive statistics were generated from the findings.
  
  
  RESULTS
  The four-factor structure of the NWI-R was not replicated in the data analysis. Instead a modified three-factor structure was identified accounting for 57% of the variance. Measures of internal consistency were acceptable.
  
  
  CONCLUSIONS
  Previous research utilised the four factors of the NWI-R as a method to identify supportive organisational context and practice. The three-factor model raises questions regarding the stability of the findings using the NWI-R. This research shows the synthesis of the two models in light of previous findings.
  
  
  CONCLUSIONS
  The findings might have far reaching implications for research that has utilised the NWI-R as a measure of organisational context. Further research is required to examine this study's findings and literature.
authors.affiliation: School of Nursing, University of Ulster, Jordanstown and Royal Hospitals Trust, Belfast, Northern Ireland. pf.slater@ulster.ac.uk
authors.forename: Paul
authors.initials: P
authors.lastname: Slater
authors.forename: Brendan
authors.initials: B
authors.lastname: McCormack
mesh_terms: D006739:Hospital Administration; D006801:Humans; D007588:Job Satisfaction; D015401:Nursing Administration Research; D009741:Nursing Staff, Hospital / Q000458:organization & administration* / Q000523:psychology / Q000600:supply & distribution; D015279:Organizational Culture; D010561:Personnel Staffing and Scheduling / Q000458:organization & administration*; D011795:Surveys and Questionnaires; D006113:United Kingdom; D016526:Workload