Table 1 Age distribution in trial groups: (a) using the sealed envelope method and (b) using central telephone randomization
From: Subversion of allocation concealment in a randomised controlled trial: a historical case study
(a) Sealed envelope method | (b) Central telephone randomisation | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Experimental | Control | Experimental | Control | |||||||||||
Clinician(s) | n | median | (IQR) | n | median | (IQR) | p | n | median | (IQR) | n | median | (IQR) | p |
All | 169 | 59 | (40, 69) | 158 | 63 | (33, 63) | <0.01 | 162 | 59 | (48, 69) | 165 | 57 | (44, 67) | 0.37 |
1 | 64 | 62 | (44, 70) | 66 | 61 | (44, 72) | 0.84 | 38 | 57 | (42, 66) | 37 | 57 | (50, 67) | 0.62 |
2 | 19 | 43 | (35, 65) | 17 | 52 | (43, 65) | 0.60 | 13 | 60 | (48, 71) | 12 | 51 | (45, 59) | 0.24 |
3 | 24 | 57 | (41, 67) | 19 | 72 | (53, 76) | <0.01 | 2 | 61 | (-) | 2 | 70 | (-) | (-) |
4 | 13 | 33 | (25, 41) | 13 | 69 | (51, 74) | <0.001 | 14 | 63 | (50, 70) | 14 | 65 | (41, 76) | 0.99 |
5 | 14 | 47 | (37, 65) | 14 | 72 | (53, 77) | 0.03 | 12 | 57 | (49, 71) | 12 | 62 | (34, 69) | 0.91 |
Others | 35 | 64 | (45, 70) | 29 | 59 | (47, 71) | 0.99 | 83 | 59 | (48, 69) | 88 | 56 | (42, 67) | 0.27 |