Table 2.

Relative risk reduction (RRR), absolute risk reduction (ARR), and number needed to treat (NNT) with respect to ulcer and/or therapy requiring dyspepsia

	RRR (%) (95% CI)	ARR (%) (95% CI)	NNT (n) (95% CI)
Ulcer
OAC-P	79 (4.5–95)	4.6 (0.7–8.5)	22 (12–143)
OAC-O	80 (11.1–96)	4.7 (0.8–8.6)	21 (12–125)
O-O	100	5.8 (2.1–9.5)	17 (11–48)
Therapy requiring dyspepsia
OAC-P	47 (8.8–69)	9.3 (1.7–17)	11 (6–59)
OAC-O	48 (11–69)	9.5 (2.0–17)	11 (6–50)
O-O	38 (-3.5–63)	7.6 (-0.3–16)	13 (6–∞)

OAC-P, one week treatment with omeprazole, amoxicillin, and clarithromycin, followed by four weeks of placebo; OAC-O, one week treatment with omeprazole, amoxicillin, and clarithromycin, followed by four weeks of omeprazole; O-O, five week treatment with omeprazole.