. Author manuscript; available in PMC: 2016 Dec 1.

Published in final edited form as: Psychooncology. 2015 Mar 13;24(12):1738–1745. doi: 10.1002/pon.3784

Table 2.

Classical reliability statistics for the Impact of Events Scale, frequency and severity versions

				Corrected item–total correlations

Scale	Cronbach’s α	ω_h	AIC	Mean	Min	Max
IES frequency	0.93 (0.91)	0.77 (0.75)	0.49 (0.41)	0.74 (0.61)	0.42 (0.34)	0.81 (0.71)
IES severity	0.97 (0.95)	0.89 (0.76)	0.69 (0.60)	0.83 (0.76)	0.76 (0.66)	0.87 (0.80)

Item–total correlations corrected for item overlap. Item statistics are based on polychoric correlations (non-polychoric statistics are in parentheses).

AIC, average interitem correlation; IES, Impact of Events Scale.