Sara Singer

Sara Singer

Professor of Medicine, Stanford School of Medicine
Professor by courtesy at the Stanford Graduate School of Business

Dissertation Title: "Safety Climate in US Hospitals: Its Measurement, Variation, and Relationship to Organizational Safety Performance"

Patient safety problems remain common in healthcare organizations. Drawing on lessons from high reliability organizations, many assume that strengthening the culture of safety in hospitals will be required to reduce errors and improve patient outcomes. However, little empirical research has (1) characterized and measured perceptions of safety culture among hospital personnel (i.e., safety climate), (2) investigated important ways in which safety climate varies within hospitals, and (3) established a link between stronger safety climate and better safety performance at the organizational level.

Using survey data collected from more than 20,000 individuals in 105 US hospitals, Chapter 2 investigates elements of organizational culture that may impact patient safety in hospitals. I identify a valid and reliable nine-dimension “Patient Safety Climate in Healthcare Organizations” (PSCHO) framework for characterizing safety climate that places constructs into three groups, reflecting organizational, work-unit, and interpersonal contributions to safety.

Chapter 3 recognizes that safety climate may vary within organizations and that understanding variation can facilitate intervention. This research focuses on variation due to an individual’s place in an institution’s management hierarchy. PSCHO survey data confirms large and consistent perceptual differences among senior managers, supervisors, and frontline workers, with senior managers consistently the most positive and frontline workers the most negative. Differences by management level, however, depend on profession, age, and gender.

Chapter 4 undertakes unprecedented research by examining the link between stronger safety climate and better safety performance among hospitals. Drawing on the insight that multiple interacting organizational layers contribute to organizational safety culture, I hypothesize that dimensions related most closely to individuals’ behaviors will be most associated with indicators of organizational safety performance, and I find this to be the case. Building on evidence of large differences in safety climate perceptions by management level, I also find that perceptions of frontline workers relate to indicators of safety performance, but those of senior managers do not. In addition, perceptions of nurses relate to nurse-sensitive indicators while no such relationship exists between physicians’ perceptions and physician-driven indicators. Together, findings offer insight into strategies for strengthening safety culture and ultimately for improving the quality and cost-effectiveness of healthcare delivery.


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