Table 4.

Odds ratio with confidence interval between demographic variables and prescription categories in 2005 and 2010.

	Odds ratio (95% CI)
	2005	2010
Sex (ref male)
Female	2.13 (1.50–3.05)	2.02 (1.55–2.62)
Age (ref 60 <)
<30	26.06 (17.05–39.82)	38.38 (25.81–57.09)
30–60	4.62 (3.11–8.59)	7.42 (5.42–5.78)
Region (ref rural)
Seoul	1.62 (1.12–2.37)	1.62 (1.18–2.22)
Metropolitan excluding Seoul	1.01 (0.68–1.51)	1.17 (0.85–1.62)
City	1.10 (0.73–1.64)	1.39 (1.02–1.89)
Types (ref medical aid)
Self-employed	2.15 (0.99–4.69)	1.08 (0.70–1.66)
The employee	2.00 (0.92–4.33)	1.44 (0.97–2.14)
Income level (ref the first)
The second	0.89 (0.52–1.54)	1.63 (1.04–2.55)
The third	0.91 (0.56–1.47)	1.34 (0.86–2.09)
The fourth	0.94 (0.59–1.47)	1.47 (0.97–2.23)
The fifth	1.14 (0.76–1.71)	1.25 (0.83–1.87)