Table 1.
Trial characteristics and designs for phase II–IV trials.
| Category | Information | Phase II(N = 586) | Phase III(N = 174) | Phase IV(N = 40) | Total (N = 800) |
|---|---|---|---|---|---|
| Allocation | Randomized, n (%) | 578(98.6%) | 174(100.0%) | 10(25.0%) | 762(95.3) |
| Not randomized, n (%) | 8(1.4%) | 0(0.0%) | 30(75.0%) | 38(4.8) | |
| Intervention model | Parallel Assignment, n (%) | 573(97.8%) | 173(99.4%) | 7(17.5%) | 753(94.1) |
| Crossover Assignment, n (%) | 2(0.3%) | 0(0.0%) | 0(0.0%) | 2(0.3) | |
| Single Group Assignment, n (%) | 10(1.7%) | 0(0.0%) | 33(82.5%) | 43(5.4) | |
| Factorial Assignment, n (%) | 1(0.2%) | 1(0.6%) | 0(0.0%) | 2(0.3) | |
| Masking | Double blind, n (%) | 557(95.1%) | 168(96.6%) | 4(10.0%) | 729(91.1) |
| Single blind, n (%) | 8(1.4%) | 4(2.3%) | 1(2.5%) | 13(1.6) | |
| Open label, n (%) | 21(3.6%) | 2(1.1%) | 35(87.5%) | 58(7.3) | |
| Test scope | Domestic, n (%) | 585(99.8%) | 172(98.9%) | 40(100.0%) | 797(99.6) |
| International Multi-center, n (%) | 1(0.2%) | 2(1.1%) | 0(0.0%) | 3(0.4) | |
| Numbers of group | One group, n (%) | 7(1.2%) | 0(0.0%) | 33(82.5%) | 40(5.0) |
| Two group, n (%) | 235(40.1%) | 139(79.9%) | 5(12.5%) | 379(47.4) | |
| Three group, n (%) | 279(47.6%) | 32(18.4%) | 1(2.5%) | 312(39.0) | |
| ≥Four group, n (%) | 65(11.1%) | 3(1.7%) | 1(2.5%) | 69(8.6) | |
| Control assignment | Placebo control only, n (%) | 417(71.2%) | 109(62.6%) | 3(7.5%) | 529(66.1) |
| Positive control only, n (%) | 90(15.4%) | 31(17.8%) | 3(7.5%) | 124(15.5) | |
| Both, n (%) | 44(7.5%) | 31(17.8%) | 0(0.0%) | 75(9.4) | |
| Neither, n (%) | 35(6.0%) | 3(1.7%) | 34(85.0%) | 72(9.0) | |
| Sample sizes | ≤ 100 cases, n (%) | 62(10.6%) | 1(0.6%) | 1(2.5%) | 64(8.0) |
| 101–300 cases, n (%) | 434(74.1%) | 21(12.1%) | 4(10.0%) | 459(57.4) | |
| 301–1000 cases, n (%) | 30(5.1%) | 134(77.0%) | 7(17.5%) | 171(21.4) | |
| >1000 cases, n (%) | 0(0.0%) | 2(1.1%) | 28(70.0%) | 30(3.8) | |
| Sample sizes | Median (IQR) | 226.5(144–240) | 480(480–550) | 767(2000–2200) | 240(144–297) |
A total of 60 and 18 phase II and phase III trials, respectively, did not provide a sample size.