Assessing vulnerability to risk of suicide and self-harm in prisoners: a Rasch analysis of the suicide concerns for offenders in the prison environment (SCOPE-2)

Table 2 Rasch results of the analysis on SCOPE

				Item Fit Residual		Person Fit Residual		Chi Square Interaction			PSI		Unidimensionality T-Tests (CI)
	Analysis	Number of items	valid n	Mean	SD	Mean	SD	Value	df	p	with extrms	NO extrms	%	lower bound 95% CI
Optimism Sample 0	Initial	15 + 1	521	1.25	2.87	−0.21	1.38	393.3	144	> 0.001	0.85	0.84	5.8%	3.9%
Optimism Sample 0	Final	10	518	0.71	0.74	−0.37	1.46	96.0	80	0.11	0.75	0.72	5.8%	3.9%
Optimism Sample 1	Initial	15 + 1	517	1.33	2.58	−0.21	1.47	411.5	144	> 0.001	0.86	0.84	7.2%	5.3%
Optimism Sample 1	Final	10	516	0.54	1.01	−0.37	1.44	74.7	80	0.65	0.77	0.73	4.8%	3.0%
Protective Self-Worth Sample 0	Initial	12 + 1	518	1.18	2.21	−0.15	1.36	228.5	117	> 0.001	0.75	0.71	4.8%	3.0%
Protective Self-Worth Sample 0	Final	9	509	0.54	1.13	−0.28	1.25	90.3	81	0.22	0.65	0.60	2.4%	0.5%
Protective Self-Worth Sample 1	Initial	12 + 1	522	1.10	2.08	−0.15	1.37	246.9	117	> 0.001	0.73	0.69	5.2%	3.3%
Protective Self-Worth Sample 1	Final	9	511	0.68	1.55	−0.30	1.33	111.9	81	0.01	0.64	0.56	1.8%	–
	Ideal Values			0	1	0	1			> 0.05	> 0.85	> 0.85	< 5%	< 5%
											> 0.7	> 0.7

ISSN: 1471-244X