. Author manuscript; available in PMC: 2020 Dec 1.

Published in final edited form as: Psychol Addict Behav. 2019 Nov 7;33(8):697–709. doi: 10.1037/adb0000521

Table 2.

DIF analyses of the CUDIT items as a function of ethnic group membership in cannabis users including men and women (2a) and men only (2b).

	2a. Men and Women (n=1960)

		Omnibus Test		a		b₁		b₂		b₃		b₄

Items		Δ χ²	p	Δ χ²	p	Δ χ²	p	Δ χ²	p	Δ χ²	p	Δ χ²	p
1	frequency of use	31.336	0.012	3.997	0.406	10.174	0.038	11.336	0.023	10.680	0.030
2	usual hours being stoned	35.324	0.004	4.042	0.400	11.120	0.025	1.871	0.759	2.235	0.693	2.082	0.721
3	stoned for 6 or more hours	35.329	0.004	0.744	0.946	3.204	0.524	1.034	0.905	1.656	0.799	2.548	0.636
4	not able to stop	-	-	-	-	-	-	-	-	-	-	-	-
5	failed to do what expected	42.917	<0.001	3.815	0.432	3.917	0.417	3.944	0.414	3.717	0.446	5.895	0.207
6	morning use	-	-	-	-	-	-	-	-	-	-	-	-
7	guilt/remorse	102.124	<0.001	0.991	0.911	14.411	0.006	6.066	0.194	4.969	0.290	6.910	0.141
8	memory/concentration problems	69.993	<0.001	2.743	0.602	9.318	0.054	2.389	0.665	1.261	0.868	3.256	0.516
10	concerned others	-	-	-	-	-	-
	2b. Men only (n=1380)

		Omnibus Test		a		b₁		b₂		b₃		b₄

Items		Δ χ²	p	Δ χ²	p	Δ χ²	p	Δ χ²	p	Δ χ²	p	Δ χ²	p

1	frequency of use	41.297	0.001	6.123	0.190	15.418	0.004	16.740	0.002	15.326	0.004
2	usual hours being stoned	33.707	0.006	4.244	0.374	8.175	0.085	1.813	0.770	3.214	0.523	4.751	0.314
3	stoned for 6 or more hours	29.482	0.021	1.389	0.846	3.637	0.457	2.120	0.714	2.769	0.597	3.615	0.461
4	not able to stop	-	-	-	-	-	-	-	-	-	-	-	-
5	failed to do what expected	32.158	0.010	3.690	0.450	3.469	0.483	4.039	0.401	3.613	0.461	4.592	0.332
6	morning use	-	-	-	-	-	-	-	-	-	-	-	-
7	guilt/remorse	84.926	<0.001	1.038	0.904	9.137	0.058	4.198	0.380	3.592	0.464	5.261	0.262
8	memory/concentration problems	55.025	<0.001	1.242	0.871	5.807	0.214	0.958	0.916	0.538	0.970	2.682	0.612
10	concerned others	-	-	-	-	-	-

Note: Δχ² – change in chi-square statistic between models freely estimating and constraining parameters to be equal; a - discrimination parameter; b_1-4 - difficulty parameters for transition between response levels for each item; bold text indicates nominal significance at p<0.05. Results for women only are not presented due to low numbers of female cannabis users. Items 4, 6, and 10 were selected as anchor items, and thus were not tested for DIF