TABLE 2.

The summary of the sub-group analysis.

—			Random effects model				Test of heterogeneity		Subgroup differences
			n	Random effect	95% CI	p-value	Heterogeneity I 2	p-value	Q	p-value
Ursolic acid treat lesions (animal studies)
IL-1β	All trials	—	69	−4.07	[-5.59; −2.54]	<0.0001	79 (%)	<0.01	—	—
	Dosage	Low (<25 mg/kg)	34	−5.91	[-8.17; −3.65]	<0.0001	68	0.01	12.05	0.002
		Middle (25–50 mg/kg)	26	−3.24	[-5.46; −1.02]	0.0043	77	<0.01
		High (>50 mg/kg)	9	−1.49	[-2.65; −0.33]	0.0116	0	0.51
SOD	All trials	—	70	3.62	[1.97; 5.26]	<0.0001	86	<0.01	—	—
	Duration	Short (≤14 days)	12	5.24	[2.32; 8.15]	0.0004	49	0.16	1.28	0.26
		Long (>14 days)	58	3.24	[1.40; 5.09]	0.0006	86	<0.01
Ursolic acid treat lesions (in vitro)
IL-1β	All trials	—	39	−5.89	[−8.24; −3.54]	<0.0001	60	<0.01
	Duration	Short (<20 h)	12	−1.85	[−3.23; −0.48]	0.008	45	0.14	18.56	<0.0001
		Middle (20–40 h)	18	−6.94	[−9.43; −4.45]	<0.0001	0	0.56
		Long (>40 h)	9	−10.28	[−15.80; −4.76]	<0.0001	0	0.88
IL-8	All trials	—	42	−6.43	[−8.91; −3.94]	<0.0001	53	<0.01	—	—
	Dosage	Low (<10 μM)	15	−4.26	[−7.23; −1.29]	0.0049	48	0.10	6.09	0.048
		Middle (10–19 μM)	6	−5.78	[−9.67; −1.88]	0.0036	0	0.79
		High (>19 μM)	21	−14.00	[−21.15; −6.86]	0.0001	38	0.14

Abbreviations: IL-1β, interleukin-1beta; SOD, superoxide dismutase; IL-8, interleukin-8.