Table 3.

Pairwise polychoric correlations among scale items

	1.	2.	3.	4.	5.	6.	7.	8.
1. loss of pleasure
2. sad/hopeless	0.65
3. sleep problems	0.43	0.48
4. tired, low energy	0.55	0.65	0.56
5. eating problems	0.47	0.53	0.55	0.64
6. feel bad about self	0.51	0.60	0.38	0.52	0.42
7. trouble concentrating	0.47	0.52	0.42	0.53	0.47	0.59
8. move slow/fidget	0.46	0.55	0.41	0.54	0.48	0.56	0.61
9. thought of death	0.48	0.65	0.40	0.50	0.44	0.55	0.48	0.56