Table 4.

Simple linear regression to assess the factors associated with the VAS score

Variable	Beta Coefficient	95% CI	P
Picture 1 (MLCon)
Picture 2 (MLon)	-0.7	-1.05, -0.35	<0.001**
Picture 3 GZ - 2	-1.86	-2.21, -1.51	<0.001**
Picture 4 GZ - 4	-2.72	-3.07, -2.67	<0.001**
Picture 5 GZ – 6	-4.34	-4.69, -3.99	<0.001**
Picture 6 RZ – 2	-2.66	-3.01, -2.31	<0.001**
Picture 7 RZ – 4	-4.70	-5.05, -4.35	<0.001**
Picture 8 RZ - 6	-7.14	-7.49, -6.79	<0.001**
Picture 2 (MLon)
Picture 1 (MLCon)	0.7	0.35, 1.05	<0.001**
Picture 3 GZ - 2	-1.16	-1.51, -0.81	<0.001**
Picture 4 GZ - 4	-2.02	-2.37, -1.67	<0.001**
Picture 5 GZ – 6	-3.64	-3.99, -3.28	<0.001**
Picture 6 RZ – 2	-1.96	-2.31, -1.61	<0.001**
Picture 7 RZ – 4	-4.00	-4.35, -3.65	<0.001**
Picture 8 RZ - 6	-6.44	-6.79, -6.09	<0.001**

n=50, SD=Standard Deviation, MLCon=Midline and chin on, MLon=Midline on, GZ=Green zone, RZ=Red zone, Simple linear regression, P≤0.05*, P≤0.001**