Table 6.

Hierarchical regression analysis using NEO-FFI scores and other variables in to predict OHIP scores before and after treatment among male participants in the study (n = 24 males).

Dependent variable	Predictors	Unstand Co		Stand Co	t	Sig	95% CI for B
		B	Std. error	Beta			Lower bound	Upper bound
OHIP before R2 = .911	(Constant)	− 15.102	17.106	–	− .883	.418	− 59.074	28.870
	Age	− 1.000	.453	− 1.290	− 2.210	.078	− 2.164	.163
	Education level	7.643	4.442	.887	1.721	.146	− 3.775	19.060
	Marital status	21.453	7.673	1.449	2.796	.038	1.730	41.177
	Smoking	7.288	3.261	.534	2.235	.076	− 1.095	15.672
	Incisor class	− 4.034	3.592	− .455	− 1.123	.312	− 13.268	5.200
	Molar class	4.265	9.073	.457	.470	.658	− 19.059	27.588
	Skeletal class	− 4.135	9.413	− .452	− .439	.679	− 28.332	20.061
	Overbite	− 3.781	3.173	− .504	− 1.192	.287	− 11.937	4.375
	Overjet	3.947	3.554	.533	1.111	.317	− 5.190	13.085
	Cross bite	4.094	11.004	.227	.372	.725	− 24.193	32.380
	Scissor bite	− 10.207	12.647	− .502	− .807	.456	− 42.717	22.304
	Extraction	4.629	3.039	.324	1.523	.188	− 3.184	12.442
	Crowding/Spacing	6.347	2.445	.716	2.595	.049	.060	12.633
	N Before	− 3.667	2.107	− .521	− 1.740	.142	− 9.083	1.750
	E Before	4.053	2.895	.468	1.400	.220	− 3.390	11.496
	O Before	5.235	2.012	.632	2.601	.048	.062	10.407
	A Before	− 5.772	4.198	− .630	− 1.375	.228	− 16.563	5.018
	C Before	− .112	2.125	− .014	− .053	.960	− 5.574	5.349
OHIP after R2 = .959	(Constant)	− 84.641	17.105		− 4.948	.004	− 128.612	− 40.671
	Age	.119	.257	.113	.461	.664	− .543	.780
	Education level	9.087	2.624	.781	3.464	.018	2.343	15.832
	Marital status	− 27.299	6.649	− 1.367	− 4.106	.009	− 44.391	− 10.207
	Smoking	7.145	2.777	.388	2.573	.050	.007	14.284
	Incisor class	19.584	3.505	1.638	5.587	.003	10.573	28.594
	Molar class	37.958	9.481	3.017	4.003	.010	13.586	62.331
	Skeletal class	− 49.067	8.924	− 3.971	− 5.499	.003	− 72.007	− 26.128
	Overbite	14.202	3.806	1.404	3.732	.014	4.419	23.984
	Overjet	− 12.780	3.816	− 1.280	− 3.349	.020	− 22.589	− 2.971
	Cross bite	− 5.932	8.916	− .243	− .665	.535	− 28.851	16.987
	Scissor bite	47.545	10.914	1.732	4.356	.007	19.489	75.601
	Extraction	− 12.616	3.481	− .655	− 3.624	.015	− 21.565	− 3.668
	Crowding/spacing	− 8.813	2.203	− .737	− 4.001	.010	− 14.476	− 3.150
	N After	− 3.328	2.074	− .298	− 1.605	.169	− 8.658	2.003
	E After	− 8.224	2.482	− .761	− 3.313	.021	− 14.605	− 1.843
	O After	21.795	4.302	1.694	5.067	.004	10.737	32.853
	A After	− 3.771	1.807	− .315	− 2.087	.091	− 8.416	.874
	C After	10.293	2.138	1.008	4.813	.005	4.796	15.790

OHIP = Oral Health Impact Profile scores, R² = Coefficient of determination, Before = Before treatment, After = After treatment, N = Neuroticism, E = Extraversion, O = Openness, A = Agreeableness, C = Conscientiousness, Unstand Co = Unstandardized coefficient, Stand Co = Standardized coefficient, B = Beta statistics, Std. Error = Standard Error, t = t statistics, Sig = Significance of probability (P value), CI = Confidence intervals. During the hierarchical multiple regression analysis, gender, age, education level, marital status, smoking, incisor class, canine class, molar class, skeletal class, overbite, overjet, cross bite, scissor bite, extraction, and crowding/spacing variables were included in the first block of independent variables and the neuroticism, extraversion, openness, agreeableness, and conscientiousness NEO-FFI dimension scores were included in the second block of independent variables to account for the confounding effects of first block variables on the contribution of NEO-FFI scores towards the OHIP scores (i.e. ability of NEO-FFI scores to predict OHIP scores).