Table 4.

Factors of willingness-to-pay for different case scenarios of glycolic acid treatment: log-gamma regression models

Variables	Case 1			Case 2			Case 3
	β	OR	P-value	β	OR	P-value	β	OR	P-value
Gender
Male	Reference			Reference			Reference
Female	−0.40	0.67	<0.001	−0.24	0.78	0.044	−0.16	0.85	0.152
Age, years
18–25	Reference			Reference			Reference
26–29	0.12	1.13	0.353	−0.17	0.840	0.189	0.03	1.03	0.804
30–39	0.40	1.50	0.042	0.06	1.057	0.784	−0.04	0.96	0.831
≥40	0.40	1.51	0.164	0.20	1.22	0.502	0.09	1.1	0.743
Marital status
Single	Reference			Reference			Reference
In a stable relationship	0.21	1.23	0.123	−0.02	0.98	0.903	0.01	1.01	0.923
Married	−0.15	0.86	0.344	−0.02	0.98	0.895	−0.08	0.92	0.596
Monthly income, USD
No stable income	Reference			Reference			Reference
<153	0.10	1.10	0.692	0.09	1.10	0.703	−0.17	0.85	0.472
154–461	−0.34	0.72	0.088	-0.18	0.84	0.372	−0.30	0.74	0.111
462–769	−0.07	0.93	0.720	0.24	1.27	0.217	−0.02	0.99	0.935
770–1,538	0.03	1.03	0.868	0.38	1.46	0.066	0.14	1.15	0.473
>1,538	0.46	1.59	0.049	0.77	2.15	0.001	0.45	1.56	0.053
History of acne
Occasionally	Reference			Reference			Reference
Frequently	−0.05	0.95	0.730	-0.05	0.95	0.715	−0.24	0.79	0.075
Self-rated acne severity
0	Reference			Reference			Reference
1	0.11	1.11	0.553	0.15	1.17	0.406	0.16	1.18	0.358
2	−0.21	0.81	0.288	-0.08	0.93	0.696	0.16	1.17	0.403
3	−0.11	0.89	0.620	0.01	1.01	0.973	0.32	1.38	0.141
4	−0.26	0.77	0.406	0.33	1.39	0.307	0.16	1.17	0.600
5	1.19	3.28	<0.001	1.53	4.62	<0.001	0.84	2.31	0.034
Cardiff Acne Disability Index	0.03	1.03	0.202	0.05	1.05	0.047	0.05	1.05	0.019
score (continuous)