Table 3.

Comparison of joint swelling improvement scores between 2 groups of patients (person) M(P25, P75).

	Control group (n = 101)	Experimental group—high concentration alkaline water (n = 100)	Experimental group—medium concentration alkaline water (n = 100)	Experimental group – low concentration alkaline water (n = 96)	H	P
Before treatment	2.47 (1.94, 3.08)	1.35 (1.11, 1.73)	2.12 (1.76, 2.46)	2.34 (1.85, 2.68)	142.86	.91
3 mo after treatment	2.34 (1.89, 2.81)	1.43 (1.09, 1.68)	1.96 (1.59, 2.25)	2.39 (1.88, 2.73)	161.90	7.12 × 10−35
6 mo after treatment	2.38 (1.98, 2.82)	1.50 (1.16, 1.88)	2.08 (1.67, 2.38)	2.27 (1.83, 2.70)	112.26	3.58 × 10−24
12 mo after treatment	2.67 (2.14, 3.03)	1.51 (1.10, 1.82)	2.01 (1.64, 2.41)	2.29 (1.89, 2.80)	131.25	2.90 × 10−28

Non-normal distribution data that do not conform to the normal distribution are described using the median (interquartile spacing) (M (P25, P75)) and independent sample Kruskal-Wallis H test. Perform inter-group comparisons for parameters with statistically significant differences.