Table 5. Response category characteristic curves for each item of K6 among hospital nurses in Vietnam.

Item	Parameter	Estimate	Standard error	Pr > |t|
k1	Threshold 1	-2.162	0.129	< .0001
	Threshold 2	-0.291	0.062	< .0001
	Threshold 3	1.564	0.101	< .0001
	Threshold 4	3.578	0.252	< .0001
	Slope	0.909	0.060	< .0001
k2	Threshold 1	0.164	0.048	0.0004
	Threshold 2	1.285	0.069	< .0001
	Threshold 3	2.420	0.128	< .0001
	Threshold 4	3.331	0.267	< .0001
	Slope	1.536	0.104	< .0001
k3	Threshold 1	-0.058	0.051	0.1256
	Threshold 2	1.320	0.075	< .0001
	Threshold 3	2.987	0.183	< .0001
	Threshold 4	3.564	0.285	< .0001
	Slope	1.320	0.087	< .0001
k4†	Threshold 1	-0.185	0.049	< .0001
	Threshold 2	1.096	0.064	< .0001
	Threshold 3	2.267	0.116	< .0001
	Slope	1.512	0.100	< .0001
k5†	Threshold 1	0.259	0.046	< .0001
	Threshold 2	1.384	0.071	< .0001
	Threshold 3	2.805	0.166	< .0001
	Slope	1.770	0.133	< .0001
k6	Threshold 1	0.853	0.058	< .0001
	Threshold 2	1.841	0.098	< .0001
	Threshold 3	2.712	0.162	< .0001
	Threshold 4	3.424	0.276	< .0001
	Slope	1.513	0.121	< .0001

† No respondent endorsed the highest response category for these items.