Table 3.
Summary of Design Features for Spinal Cord Injury Trials in ClinicalTrials.gov
| Feature | Total count | % | Pre-2007 count | % | 2007+ count | % | % Change | p Value |
|---|---|---|---|---|---|---|---|---|
| Study type | 0.16 | |||||||
| Interventional | 225 | 78.1 | 94 | 81.7 | 124 | 74.7 | 31.9 | |
| Observational | 63 | 21.9 | 21 | 18.3 | 42 | 25.3 | 100.0 | |
| Allocation | 0.09 | |||||||
| Randomized | 147 | 73.1 | 57 | 66.3 | 91 | 77.1 | 59.6 | |
| Non-randomized | 54 | 26.9 | 29 | 33.7 | 27 | 22.9 | −6.9 | |
| Masking | 0.01 | |||||||
| Open label | 116 | 53.5 | 56 | 63.6 | 63 | 47.4 | 12.5 | |
| Double-blind | 62 | 28.6 | 24 | 27.3 | 39 | 29.3 | 62.5 | |
| Single-blind | 39 | 18.0 | 8 | 9.1 | 31 | 23.3 | 287.5 | |
| Control | 0.34 | |||||||
| Active control | 55 | 36.7 | 29 | 40.3 | 23 | 34.3 | −20.7 | |
| Placebo control | 49 | 32.7 | 20 | 27.8 | 27 | 40.3 | 35.0 | |
| Uncontrolled | 30 | 20.0 | 16 | 22.2 | 10 | 14.9 | −37.5 | |
| Dose comparison | 13 | 8.7 | 5 | 6.9 | 7 | 10.4 | 40.0 | |
| Historical control | 3 | 2.0 | 2 | 2.8 | 0 | 0.0 | −100.0 | |
| Design | 0.09 | |||||||
| Parallel assignment | 96 | 44.9 | 33 | 37.9 | 64 | 48.9 | 93.9 | |
| Single group assignment | 79 | 36.9 | 40 | 46.0 | 42 | 32.1 | 5.0 | |
| Crossover assignment | 36 | 16.8 | 12 | 13.8 | 24 | 18.3 | 100.0 |
After study type, all features relate to interventional studies. Counts are numbers of trials. p Values calculated by chi-square test indicate differences between pre-2007 trials and trials from 2007 onward. Categories with counts <10 were not included in p-value calculations. Pre-2007 and post-2007 sums may not match totals since some trials did not report start dates.