Table 3. Mean positive responses of nurses to levels of patient safety culture in Urmia training hospitals .

Safety culture levels	Score	Positive response	95% confidence interval
Unit level (7 dimensions)	58.90 (0.51)	932 (58.82)	58.87-58.93
Hospital level (3 dimensions )	55.05 (0.88)	919 (54.95)	54.99-55.11
Outcome variable (2 dimensions)	52.90 (0.83)	926 (52.27)	52.85-52.95
Overall perceptions of patient safety	56.90 (0.54)	932 (55.34)	53.43-60.37
Values are expressed as mean (SD) or n (%).