Table 2.

Corrected item-total and squared multiple correlations, evaluating each individual item against the total score of the remaining 12 items, in 3 independent samples of 130 subjects (10 subjects per item).

	Corrected item-total correlation (N = 130 each)
	Sample 1	Sample 2	Sample 3
1. I worry all the time about whether the pain will end	0.70 (0.60)	0.58 (0.50)	0.75 (0.59)
2. I feel I can’t go on	0.74 (0.62)	0.66 (0.57)	0.73 (0.61)
3. It’s terrible and I think it’s never going to get any better	0.73 (0.67)	0.72 (0.69)	0.82 (0.74)
4. It’s awful and I feel that it overwhelms me	0.84 (0.76)	0.80 (0.77)	0.81 (0.75)
5. I feel I can’t stand it anymore	0.79 (0.71)	0.69 (0.62)	0.79 (0.69)
6. I become afraid that the pain will get worse	0.73 (0.60)	0.54 (0.36)	0.78 (0.67)
7. I keep thinking of other painful events	0.55 (0.49)	0.48 (0.34)	0.54 (0.40)
8. I anxiously want the pain to go away	0.64 (0.58)	0.65 (0.49)	0.68 (0.59)
9. I can’t seem to keep it out of my mind	0.64 (0.58)	0.66 (0.58)	0.83 (0.77)
10. I keep thinking about how much it hurts	0.70 (0.71)	0.69 (0.61)	0.83 (0.78)
11. I keep thinking about how badly I want the pain to stop	0.76 (0.75)	0.72 (0.61)	0.79 (0.72)
12. There’s nothing I can do to reduce the intensity of the pain	0.60 (0.48)	0.52 (0.33)	0.68 (0.51)
13. I wonder whether something serious may happen	0.64 (0.58)	0.55 (0.39)	0.69 (0.54)

All values are Pearson’s r. Italics: Items that did not reach the a priori threshold for retention of mean item-total correlation at least r = 0.70. Bolded: Items that were retained to move onto Rasch analysis on the basis of either statistical or conceptual considerations