Table 2.

Summary of meta-analysis between NAT2 acetylator status and overall adverse drug reactions of sulfasalazine.

NAT2 acetylator status comparison	Number of studies	First comparator		Second comparator		I2 (%)	Statistical model	Odds ratio (95% CI)	p-value
		Case	Control	Case	Control
SAs vs RAs	5	21	54	29	201	24	Fixed	3.56 (1.73–7.35)	0.0006
SAs vs IAs	5	21	54	26	199	58	Random	4.70 (1.24–17.89)	0.02
IAs vs RAs	5	26	199	29	201	0	Fixed	1.01 (0.57–1.82)	0.96

RAs: rapid acetylators; IAs: intermediate acetylators; SAs: slow acetylators.