Table 1.

Item content, scale source, study source, proportion endorsed, and IRT item parameters for the 21 internalizing symptomatology items

#	Item	Scale	Study Source	Proportion Endorsed	IRT Discrimination	IRT Severity
1	hopeless about future	BSI	MLS / AHBP	.16	2.19	1.26
2	scared for no reason	BSI	MLS / AHBP	.08	2.00	1.86
3	blue	BSI	MLS / AHBP	.34	1.92	0.55
4	no interest in things	BSI	MLS / AHBP	.24	1.65	1.00
5	terror / panic	BSI	MLS / AHBP	.03	2.09	2.43
6	restless	BSI	MLS / AHBP	.21	1.15	1.41
7	Cries a lot	CBCL	MLS / AFDP	.17	1.41	1.47
8	might think / do something bad	CBCL	MLS	.17	1.31	1.56
9	have to be perfect	CBCL	MLS / AFDP	.36	1.06	0.64
10	no one loves me	CBCL	MLS / AFDP	.10	2.70	1.53
11	feel guilty	CBCL	MLS / AFDP	.15	1.45	1.60
12	Unhappy / sad / depressed	CBCL	MLS / AFDP	.25	2.96	0.79
13	Worried	CBCL	MLS / AFDP	.35	1.83	0.52
14	others out to get me	CBCL	MLS	.11	1.65	1.79
15	suspicious	CBCL	MLS	.39	1.21	0.49
16	lonely	CBCL / BSI	MLS / AFDP / AHBP	.32	2.13	0.60
17	worthless / inferior	CBCL / BSI	MLS / AFDP / AHBP	.13	3.26	1.27
18	Nervous / tense	CBCL / BSI	MLS / AFDP / AHBP	.44	1.52	0.22
19	Fearful / anxious	CBCL / BSI	MLS / AFDP / AHBP	.19	1.80	1.21
20	Self-conscious / easily embarrassed	CBCL / BSI	MLS / AHBP	.39	1.51	0.43
21	Thinks about killing self	CBCL / BSI	MLS / AHBP	.06	2.04	2.07

note: MLS=Michigan Longitudinal Study; AFDP=Adolescent / Adult Family Development Project; AHBP=Alcohol and Health Behavior Project; Total sample size for proportion endorsed and IRT parameters N = 1827; MLS N = 512; AFDP N =830; AHBP N = 485; for items 16 through 19, AFDP items were drawn from the CBCL, AHBP from the BSI, and MLS from both the CBCL and BSI;