Table 2

Number needed to treat for at least 50% pain relief


Improved with
 % improved





Number of trials
 Drug and dose (mg)
 Active
 Placebo
 Active
 Placebo
 Relative risk (95% CI)
 NNT (95% CI)
Six hour ourcomes
     1
 Rofecoxib 25
 66/115
 45/118
 57
 38
 1.5 (1.1 to 2.0)
 5.0 (3.7 to 7.8)
     3
 Rofecoxib 50
 140/226
 70/225
 62
 31
 2.0 (1.6 to 2.5)
 3.2 (2.4 to 4.5)
     1
 Ibuprofen 400
 31/49
 10/47
 63
 21
 3.0 (1.7 to 5.4)
 2.4 (1.7 to 4.2)
     2
 Naproxen sodium 550
 120/181
 60/178
 66
 34
 2.0 (1.6 to 2.5)
 3.1 (2.4 to 4.4)
Eight hour ourcomes
     1
 Rofecoxib 25
 70/115
 44/118
 61
 37
 1.6 (1.2 to 2.2)
 4.2 (2.8 to 9.0)
     3
 Rofecoxib 50
 147/226
 73/225
 65
 32
 2.0 (1.6 to 2.5)
 3.1 (2.4 to 9.0)
     1
 Ibuprofen 400
 30/47
 11/47
 61
 21
 2.6 (1.5 to 4.6)
 2.6 (1.8 to 5.1)
     2
 Naproxen sodium 550
 121/181
 62/178
 68
 35
 2.0 (1.6 to 2.4)
 3.0 (2.3 to 4.3)
Twelve hour ourcomes
     1
 Rofecoxib 25
 64/115
 45/118
 56
 38
 1.5 (1.1 to 1.9)
 5.7 (3.3 to 20)
     3
 Rofecoxib 50
 135/226
 74/225
 60
 33
 1.8 (1.5 to 2.3)
 3.7 (2.8 to 5.6)
     1
 Ibuprofen 400
 27/49
 12/47
 55
 26
 2.2 (1.3 to 3.7)
 3.4 (2.1 to 9.2)
     2
 Naproxen sodium 550
 111/181
 62/178
 61
 35
 1.8 (1.4 to 2.2)
 3.8 (2.7 to 6.1)

Edwards et al. BMC Women's Health 2004 4:5   doi:10.1186/1472-6874-4-5