Table 5.

Internal consistency of subscales of the Depression Anxiety Stress Scale 21 and shortened versions in the samples.

Criteria	Samples	DASS-21			Korean DASS-12			DASS-13		Osman’s DASS-9			DASS-9			DASS-8
		Depression	Anxiety	Stress	Depression	Anxiety ▲	Stress	Depression	Stress	Depression	Anxiety	Stress	Depression	Anxiety △	Stress △	Depression
Coefficient alpha	Sample 1	0.902	0.872	0.908	0.850	0.772	0.852	0.898	0.824	0.833	0.731	0.695	0.869	0.888	0.835	0.854
	Sample 2	0.854	0.795	0.891	0.742	0.626	0.828	0.846	0.814	0.753	0.554	0.766	0.777	0.789	0.801	0.793
Range of corrected item-total correlations	Sample 1	0.607–0.797	0.496–0.748	0.577–0.820	0.653–0.741	0.497–0.641	0.579–0.766	0.665–0.793	0.599–0.780	0.604–0.708	0.484–0.611	0.533-	0.667–0.765	0.720–0.829	All 0.717	0.706–0.740
	Sample 2	0.468–0.707	0.349–0.667	0.574–0.788	0.416–0.606	0.350–0.459	0.561–0.768	0.443–0.707	0.614–0.744	0.404–0.631	0.319–0.400	0.623	0.443–0.659	0.580–0.696	All 0.668	0.595–0.673
Range of alpha if-item-deleted	Sample 1	0.877–0.898	0.840–0.873	0.884–0.910	0.788–0.826	0.680–0.755	0.779–0.856	0.869–0.889	0.695–0.835	0.770–0.815	0.580–0.722	--	0.820–0.845	0.801–0.895	-	0.782–0.814
	Sample 2	0.820–0.856	0.740–0.801	0.862–0.889	0.641–0.751	0.516–0.602	0.734–0.827	0.805–0.857	0.667–0.801	0.650–0.778	0.409–0.528	--	0.682–0.793	0.647–0.780	-	0.676–0.759
Correlation with the corresponding scale on the DASS-21	Sample 1	--	--	--	0.970	0.897	0.969	0.991	0.943	0.963	0.866	0.884	0.967	0.924	0.921	0.949
	Sample 2	--	--	--	0.947	0.828	0.955	0.979	0.899	0.906	0.799	0.832	0.958	0.837	0.863	0.899
Correlation with the DASS-21	Sample 1	0.952	0.935	0.958	0.918	0.796	0.926	0.943	0.895	0.911	0.769	0.830	0.918	0.902	0.881	0.904
	Sample 2	0.914	0.823	0.939	0.866	0.613	0.900	0.898	0.828	0.805	0.587	0.766	0.881	0.770	0.808	0.854

▲: Items on the anxiety subscale on the DASS-12 and the DASS-13 are the same, △: items on the anxiety and stress subscales on the modified DASS-9 and the DASS-8 are the same, all correlations are significant at the 0.01 level.