1. Understanding the Influences on the Association between Nurse Staffing and Preventable Patient Complications Deborah Dang, PhD, RN 2007 Interdisciplinary Research Interest Group on Nursing Issues Academy Health June 2, 2007

2. Problem and Significance Nurse staffing may be necessary, but not sufficient, to prevent adverse patient events Few studies have examined characteristics of the work environment at the unit level that may affect staffing Nurse staffing and characteristics of the work environment are modifiable features in hospitals

3. Purpose Examine the impact of nurse staffing and potential confounders on preventable adverse events at the unit level over a seven year period.

4. Research Questions 1. Is unit-level nurse staffing associated with the failure to rescue, falls, and medication errors between 1998 and 2004? 2. Do unit characteristics confound the relationship between nurse staffing and adverse events between 1998 and 2004?

5. Central line-associated BSIs ++ Decubitus ulcer + Falls+ Failure to rescue ++ Medication errors + Mortality+ Pneumonia, hospital acquired + Pneumonia, vent-associated + Post-op PE/DVT + Post-op respiratory failure + UTI, catheter-associated ++ Staffing and Strength of Staffing and Strength of Patient Outcomes Evidence ++ consistent evidence; + mixed evidence

6. Conceptual Model System Outcome Intervention Client Quality Health Outcomes Model (Mitchell, Freketich, & Jennings, 1998)

7. Study Model System Unit Nurse Staffing Characteristics Total hours  Agency proportion RN hours  Orientee proportion RN Proportion  RN education RN shortfall  RN experience  RN turnover  Patient turnover Outcomes Adverse Events Failure to rescue Falls Medication errors

8. Research Design Design Descriptive correlational using secondary data Setting 945 bed, Magnet-designated, not-for-profit, urban academic medical center Sample Convenience sample of 31 adult and pediatric inpatient units Unit of analysis Care-giving unit

9. Type of Patients and Level of Care Adult units: 25 (84%) Acute care: 16 (52%) IMC: 8 (26%) ICU: 7 (23%) * > 100% due to rounding

10. File Development Design and construct the database and merge procedures Restructure database Develop procedures for handling: Changes in cost centers Inconsistent reporting periods Handling missing data Construct 3 separate files for analyses: Failure to rescue (N = 28) Falls (n=560) Medication errors (n = 341)

11. Analyses Hospital-level: Failure to Rescue –Descriptive –Bivariate: zero-order and first-order correlations Unit-level: Falls and Medication errors –Poisson regression with a robust variance estimator –Adjust for type of unit –Account for change in AE rates over time by including a quadratic function of time

12. Sample Benchmarks Total HPPD RN Proportion (%) AcuteIMCICUAcuteIMCICU Current study (31 units) 8.712.721.581.583.787.5 Dunton (1751 units) 7.6*9.1*15.9*63.669.789.2 Blegen (39 units) 8.618.069.090.0 *Median

13. Unit Characteristics Overall Mean Agency proportion, % 10.06 Orientation proportion, % 5.04 RN education, % BSN 77.66 RN experience, years 7.77 RN turnover, % 9.32 Patient turnover, ADT* 9.12 *admissions, discharges, transfers

14. Rate of Failure to Rescue

15. Correlation: FTR and Staffing Zero-order Correlation R2R2R2R2 Total hours -.795**.63 RN hours -.797**.64 RN proportion -.085 -.085.01 RN shortfall.678**.678**.46

16. *p <.05, **p <.01 First-order Correlation FTR and Staffing Removing: Removing: Zero-orderCorrelation Agency Proportion RN Turnover Total hours (R 2 ) -.795**(.63)-.756**(.57)-.762**(.58) RN hours (R 2 ) -.797**(.64)-.757**(.57)-.767**(.59) RN shortfall (R 2 ).678**.678**(.46)-.679**(.46).654**.654**(.43)

17. Rate of Falls by Type of Unit (n = 560)

18. Relative Rate of Falls for each 10% Increase in Staffing Unadjusted and Adjusted Relative Rates

19. Rate of Medication Errors by Type of Unit (n = 341)

20. Relative Rate of Medication Errors for each 10% increase in Staffing Unadjusted and Adjusted Relative Rates

21. Summary of Findings Staffing effect found for all AEs RN shortfall effect found for FTR and falls Unit characteristics had little to no influence on association between staffing and AEs Unclear explanation for findings in unexpected direction

22. Limitations Measurement error Risk adjustment for falls and medication errors Other unmeasured factors Generalizability

23. Implications for Practice Longitudinal data presented opportunity to explore multiple predictors at the unit level Investment needed by hospitals to collect and monitor unit-level data Unique conceptualization and measurement of staffing

24. Future Research Unit-level risk adjustments methods Large scale unit-level studies Attribution of failure to rescue to unit-level Impact of organizational factors on staffing and patient outcomes

25. Questions