title: An empirical test of the Nursing Role Effectiveness Model.
abstract: OBJECTIVE
  This study investigated the propositions depicted in the Nursing Role Effectiveness Model, in which nurse and patient structural variables were expected to influence nurses' role performance, which, in turn was expected to affect patient outcome achievement. RATIONALE/BACKGROUND: Increasingly, nurses are expected to demonstrate their contribution to patient outcome achievement as a basis for evaluating practice and for monitoring improvements in practice. A model was developed that describes nursing practice in relationship to the roles nurses assume in health care, and links patient and system outcomes to nurses' role functions (Nursing Economics 1998: 16, 58-64, 87).
  
  
  METHODS
  A cross-sectional design was used to collect data on the structure, process, and outcome variables. Data were collected through structured questionnaires and chart audit, involving a total of 372 patients and 254 nurses from 26 general medical-surgical units in a tertiary care hospital. Patient structural variables included medical diagnosis, age, gender and education. Nurse structural variables included educational preparation and length of hospital experience. The unit structural variables included the adequacy of time to provide care, autonomy, and role tension. The quality of nurses' independent role performance was assessed by collecting data from patients on their perception of the quality of nursing care. Nurses' interdependent role performance was assessed by collecting data from nurses on the quality of nurse communication and co-ordination of care. Patient outcomes were assessed through self-report and consisted of the patients' therapeutic self-care ability, functional status, and mood disturbance at the time of hospital discharge. Structural equation modelling was used to test the hypothesized relationships among the structural, process, and outcome variables.
  
  
  RESULTS
  Patients viewed nurses' independent role performance more effective on units where nurses reported less autonomy but more time to provide care. The quality of nurse communication was higher on units where nurses had higher education, more autonomy, less hospital experience, and lower role tension. However, the co-ordination of care was more effective on units where nurses had higher education, greater hospital experience, less autonomy and role tension. The three role performance variables were associated with patients' therapeutic self-care ability at hospital discharge. Nurses' independent role performance was associated with better patient functional status and less mood disturbance at hospital discharge. The role performance variables fully mediated the effect of the structural variables on patient outcomes, lending support for the proposition that nurses' role performance explains the relationship between structural variables, such as nurse education and autonomy, and patient outcome achievement.
  
  
  CONCLUSIONS
  The Nursing Role Effectiveness Model provides a well-defined conceptual framework to guide the evaluation of outcomes of nursing care. For the most part the hypothesized relationships among the variables were supported. However, further work is needed to develop an understanding of how nurses engage in their co-ordinating role functions and how we can measures these role activities.
authors.affiliation: Nursing Effectiveness, Utilization, and Outcomes Research Unit, Faculty of Nursing, University of Toronto, Toronto, Ontario, Canada. diane.doran@utoronto.ca
authors.forename: Diane Irvine
authors.initials: DI
authors.lastname: Doran
authors.forename: Souraya
authors.initials: S
authors.lastname: Sidani
authors.forename: Margaret
authors.initials: M
authors.lastname: Keatings
authors.forename: Doris
authors.initials: D
authors.lastname: Doidge
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016294:Models, Nursing; D024802:Nurse's Role; D009723:Nurse-Patient Relations; D009731:Nursing Audit; D017063:Outcome Assessment, Health Care / Q000592:standards*; D017009:Professional Autonomy; D011795:Surveys and Questionnaires