Table 5 A comparison of current practice with a review conducted in 2014
|  | Study Characteristic | 2014 (n = 167)a | 2014 with HTA (n = 196)a | 2019 (n = 385)a |
|---|---|---|---|---|
Cluster Randomised | No | 160 (96) | 184 (93) | 348 (90) |
Yes | 7 (4) | 12 (7) | 37 (10) | |
Covariates included in the allocation | No | 15 (10) | 21 (11) | 73 (19) |
Yes | 139 (90) | 162 (89) | 312 (81) | |
Number of covariates | 1 | 53 (38) | 63 (38) | 121 (31) |
2 | 54 (39) | 57 (34) | 86 (23) | |
3 | 23 (17) | 25 (15) | 61 (16) | |
4 | 6 (4) | 8 (5) | 24 (6) | |
5 +  | 3 (2) | 14 (8) | 93 (24) | |
Number of Centres | Single Centre | 9 (5) | 18 (9) | 67 (17) |
Multicentre | 158 (95) | 178 (91) | 318 (83) | |
Number of Arms | 2 | 129 (77) | 149 (76) | 319 (83) |
3 | 16 (10) | 23 (12) | 45 (12) | |
4 | 14 (8) | 16 (9) | 15 (4) | |
5 +  | 8 (5) | 8 (4) | 6 (1) | |
Allocation Method | Purely Random | 1 (1) | 2 (1) | 25 (6) |
Blocked | 15 (10) | 20 (11) | 35 (9) | |
Stratified or Stratified Block | 123 (79) | 135 (74) | 244 (64) | |
Minimisation/Covariate adaptive | 14 (9) | 23 (13) | 57 (15) | |
Other | 2 (1) | 3 (1) | 24 (6) |