In this study, the medical department with worse safety culture scores, as rated by AHRQ Hospital Survey of Patient Safety Culture, actually had fewer adverse events, as measured by the Institute for Healthcare Improvement's Global Trigger Tool. The authors suggest that safety culture may not accurately reflect patient safety and requires further measure development.

Nursing skill mix and training may be linked to patient outcomes, and one study showed lower inpatient mortality rates for a variety of surgical patients in hospitals with more highly educated nurses. In this study, practicing nurses had greater medication knowledge than graduating nursing students, but both groups had serious deficiencies, particularly in their ability to perform drug dose calculations correctly.