Table 5. Outpatient services: the description of independent variables in the linear regression models.

Variables	Description	Percentage (%)
Year
2010*	2010 = 1, 2011 = 0	50.0
2011	2011 = 1, 2010 = 0	50.0
Gender
Female*	Female = 1, male = 0	40.4
Male	Male = 1, female = 0	59.6
Age
0 to 6 years old*	0 to 6 years old = 1, other = 0	36.8
7 to 17 years old	7 to 17 years old = 1, other = 0	20.2
18 to 40 years old	18 to 40 years old = 1, other = 0	30.0
41 to 65 years old	41 to 65 years old = 1, other = 0	11.6
More than 65 years old	More than 65 years old = 1, other = 0	1.5
Surgery
No surgery*	No surgery = 1, surgery = 0	98.2
Surgery	Surgery = 1, no-surgery = 0	1.8

Note: * stands for the reference group in regressions.