Perhaps unfairly, doctors get all the credit. When patients have better health outcomes, physicians are rewarded; when they have worse health outcomes, the physician is blamed. However, the quality of nurses also likely affects the quality of care that patients receive. A recent paper by Yakusheva, Lindrooth and Weiss (2014) finds that nurse quality does affect outcomes. Using an EHR-based measure of patient health (the Rothman Index), the authors find the following:
Nurse effects were jointly significant and explained 7.9 percent of variance in patient clinical condition change during hospitalization. NVA was positively associated with having a baccalaureate degree or higher (0.55, p = .04) and expertise level (0.66, p = .03). NVA contributed to patient outcomes of shorter length of stay and lower costs.
One issue not addressed is nurse assignment to patients. The empirical approach basically assumes that nurse assignment to patients is uncorrelated with nurse quality. In reality, the highest quality nurses may take the most difficult cases in some hospitals. One might believe that the highest quality nurses would be assigned to case where they would have the largest improvement in outcomes. However, management’s utility function may not be linear in patient outcomes. For instance, management may assign high-quality nurses to critically ill patients and these high-quality nurses may move the patients from critically ill to sick; a feat that may not be feasible for low-quality nurses. Low quality nurses could move moderately ill patients to excellent health, but this feat may be easier than moving patients from critically ill to sick. Thus, if risk adjustment is inadquate, high quality nurses may be more valueable even then the figures from this study state.
One conclusions that the authors incorrectly draw is that their results “…strengthen the body of evidence in support of strategic federal, state, and health system initiatives to build toward a baccalaureate-educated workforce.” Although it is true that nurses with a BA are more likely to be high-performing nurses, there is no evidence that getting a BA has a causal effect on outcomes; nurses who were motivated to get a BA were likely going to be the best nurses regardless of the education received.
Although these results are not surprising–high-quality nursing should clearly result in better patient outcomes than low-quality–this study does make the important point that physicians are not the only healthcare providers who play an important role in hospitalized patients’ health outcomes.