Journal (N in cohort) | Total (N = 264) | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
BMJ (N = 16) | NEJM (N = 55) | Lancet (N = 66) | HTA (N = 127) | |||||||||
n | n/N% | n | n/N% | n | n/N% | n | n/N% | n | n/N% | |||
Trial rationale | Explanatory | 0 | 0.0 | 0 | 0.0 | 5 | 7.6 | 2 | 1.6 | 7 | 2.7 | |
Pragmatic | 6 | 37.5 | 2 | 3.6 | 10 | 15.2 | 88 | 69.3 | 106 | 40.2 | ||
Not specified or clear | 10 | 62.5 | 53 | 96.4 | 51 | 77.3 | 37 | 29.1 | 151 | 57.2 | ||
Funder origin | Asia | 0 | 0.0 | 1 | 1.8 | 3 | 4.5 | 0 | 0.0 | 4 | 1.5 | |
Japan | 0 | 0.0 | 1 | 1.8 | 2 | 3.0 | 0 | 0.0 | 3 | 1.1 | ||
South Korea | 0 | 0.0 | 0 | 0.0 | 1 | 1.5 | 0 | 0.0 | 1 | 0.4 | ||
Australia | 1 | 6.3 | 2 | 3.6 | 3 | 4.5 | 0 | 0.0 | 6 | 2.3 | ||
Australia | 1 | 6.3 | 2 | 3.6 | 2 | 3.0 | 0 | 0.0 | 4 | 1.5 | ||
New Zealand | 0 | 0.0 | 0 | 0.0 | 1 | 1.5 | 0 | 0.0 | 2 | 0.8 | ||
Europe | 14 | 87.5 | 21 | 38.2 | 40 | 60.6 | 127 | 100.0 | 202 | 76.5 | ||
Belgium | 0 | 0.0 | 1 | 1.8 | 0 | 0.0 | 0 | 0.0 | 1 | 0.4 | ||
Denmark | 3 | 18.8 | 2 | 3.6 | 0 | 0.0 | 0 | 0.0 | 5 | 1.9 | ||
Finland | 1 | 6.3 | 0 | 0.0 | 0 | 0.0 | 0 | 0.0 | 1 | 0.4 | ||
France | 0 | 0.0 | 2 | 3.6 | 5 | 7.6 | 0 | 0.0 | 7 | 2.7 | ||
Germany | 0 | 0.0 | 1 | 1.8 | 6 | 9.1 | 0 | 0.0 | 7 | 2.7 | ||
Ireland | 1 | 6.3 | 0 | 0.0 | 2 | 3.0 | 0 | 0.0 | 3 | 1.1 | ||
Netherlands | 2 | 12.5 | 1 | 1.8 | 2 | 3.0 | 0 | 0.0 | 5 | 1.9 | ||
Spain | 0 | 0.0 | 0 | 0.0 | 1 | 1.5 | 0 | 0.0 | 1 | 0.4 | ||
Sweden | 0 | 0.0 | 0 | 0.0 | 1 | 1.5 | 0 | 0.0 | 1 | 0.4 | ||
Switzerland | 1 | 6.3 | 4 | 7.3 | 3 | 4.5 | 0 | 0.0 | 8 | 3.0 | ||
United Kingdom | 6 | 37.5 | 9 | 16.4 | 19 | 28.8 | 127 | 100.0 | 161 | 61.0 | ||
Other (European Union) | 0 | 0.0 | 1 | 1.8 | 1 | 1.5 | 0 | 0.0 | 2 | 0.8 | ||
North America | 1 | 6.3 | 30 | 54.5 | 20 | 30.3 | 0 | 0.0 | 51 | 19.3 | ||
Canada | 0 | 0.0 | 1 | 1.8 | 0 | 0.0 | 0 | 0.0 | 1 | 0.4 | ||
United States of America | 1 | 6.3 | 29 | 52.7 | 20 | 30.3 | 0 | 0.0 | 50 | 18.9 | ||
Not specified | 0 | 0.0 | 1 | 1.8 | 0 | 0.0 | 0 | 0.0 | 1 | 0.4 | ||
Recruitment setting | Primary | 4 | 25.0 | 2 | 3.6 | 5 | 7.6 | 46 | 36.2 | 57 | 21.6 | |
Secondary only | 2 | 12.5 | 2 | 3.6 | 5 | 7.6 | 17 | 13.4 | 26 | 9.8 | ||
Tertiary only | 3 | 18.8 | 17 | 30.9 | 30 | 45.5 | 47 | 37.0 | 97 | 36.7 | ||
Secondary or tertiary (not specified) | 0 | 0.0 | 0 | 0.0 | 2 | 3.0 | 3 | 2.4 | 5 | 1.9 | ||
Community | 7 | 43.8 | 4 | 7.3 | 2 | 3.0 | 15 | 11.8 | 28a | 10.6 | ||
Emergency | 1 | 6.3 | 5 | 9.1 | 0 | 0.0 | 7 | 5.5 | 13 | 4.9 | ||
Hospice | 0 | 0.0 | 0 | 0.0 | 0 | 0.0 | 0 | 0.0 | 0 | 0.0 | ||
Social care | 0 | 0.0 | 0 | 0.0 | 0 | 0.0 | 0 | 0.0 | 0 | 0.0 | ||
Other setting | 0 | 0.0 | 1 | 1.8 | 1 | 1.5 | 0 | 0.0 | 2b | 0.8 | ||
Not clear | 0 | 0.0 | 32 | 58.2 | 22 | 33.3 | 9 | 7.1 | 63c | 23.9 | ||
Trial design | Parallel | 13 | 81.3 | 48 | 87.3 | 59 | 89.4 | 103 | 81.1 | 233 | 88.3 | |
Sequential | 0 | 0.0 | 1 | 1.8 | 1 | 1.5 | 1 | 0.8 | 3 | 1.1 | ||
Crossover | 0 | 0.0 | 1 | 1.8 | 2 | 3.0 | 5 | 3.9 | 9 | 3.4 | ||
Cluster | 2 | 12.5 | 0 | 0.0 | 2 | 3.0 | 11 | 8.7 | 15 | 5.7 | ||
Factorial | 1 | 6.3 | 5 | 9.1 | 2 | 3.0 | 7 | 5.5 | 15 | 5.7 | ||
Number of trial arms | 2 | 12 | 75.0 | 42 | 76.4 | 46 | 69.7 | 85 | 66.9 | 185 | 70.1 | |
3 | 3 | 18.8 | 7 | 12.7 | 10 | 15.2 | 29 | 22.8 | 49 | 18.6 | ||
4 | 1 | 6.3 | 4 | 7.3 | 4 | 6.1 | 7 | 5.5 | 16 | 6.1 | ||
5 | 0 | 0.0 | 2 | 3.6 | 2 | 3.0 | 5 | 3.9 | 9 | 3.4 | ||
6 or more | 0 | 0.0 | 0 | 0.0 | 4 | 6.1 | 1 | 0.8 | 5d | 1.9 | ||
Type of intervention e, f | Pharmaceutical | 3 | 18.8 | 41 | 74.5 | 54 | 81.8 | 34 | 26.8 | 132 | 50.0 | |
Cellular and gene therapy | 0 | 0.0 | 1 | 1.8 | 2 | 3.0 | 0 | 0.0 | 3 | 1.1 | ||
Medical device | 0 | 0.0 | 5 | 9.1 | 5 | 7.6 | 16 | 12.6 | 26 | 9.8 | ||
Surgery | 0 | 0.0 | 3 | 5.5 | 1 | 1.5 | 10 | 7.9 | 14 | 5.3 | ||
Radiotherapy | 0 | 0.0 | 1 | 1.8 | 3 | 4.5 | 9 | 7.1 | 13 | 4.9 | ||
Psychological and behavioural | 6 | 37.5 | 0 | 0.0 | 1 | 1.5 | 22 | 17.3 | 29 | 11.0 | ||
Physical | 2 | 12.5 | 2 | 3.6 | 0 | 0.0 | 10 | 7.9 | 14 | 5.3 | ||
Complimentary | 0 | 0.0 | 0 | 0.0 | 1 | 1.5 | 5 | 3.9 | 6 | 2.3 | ||
Resources and infrastructure | 1 | 6.3 | 1 | 1.8 | 1 | 1.5 | 19 | 15.0 | 22 | 8.3 | ||
Other | 4 | 25.0 | 2 | 3.6 | 1 | 1.5 | 12 | 9.4 | 19 | 7.2 | ||
Number of primary outcomes | 1 | 11 | 68.8 | 47 | 85.5 | 51 | 77.3 | 101 | 79.5 | 210 | 79.5 | |
2 | 2 | 12.5 | 3 | 5.5 | 10 | 15.2 | 13 | 10.2 | 28 | 10.6 | ||
3 | 1 | 6.3 | 4 | 7.3 | 2 | 3.0 | 1 | 0.8 | 8 | 3.0 | ||
4 or more | 2 | 12.5 | 1 | 1.8 | 2 | 3.0 | 11 | 8.7 | 16 | 6.1 | ||
Primary outcome type | Subjective | 1 primary outcome | 3 | 18.8 | 0 | 0.0 | 2 | 3.0 | 39 | 30.7 | 44 | 16.7 |
2 + primary outcomes | 1 | 6.3 | 0 | 0.0 | 0 | 0.0 | 4 | 3.1 | 5 | 1.9 | ||
Objective | 1 primary outcome | 6 | 37.5 | 46 | 83.6 | 46 | 69.7 | 53 | 41.7 | 151 | 57.2 | |
2 + primary outcomes | 3 | 18.8 | 6 | 10.9 | 13 | 19.7 | 6 | 4.7 | 28 | 10.6 | ||
Both | 1 primary outcome | 0 | 0.0 | 0 | 0.0 | 0 | 0.0 | 3 | 2.4 | 3g | 1.1 | |
2 + primary outcomes | 1 | 6.3 | 2 | 3.6 | 1 | 1.5 | 14 | 11.0 | 18 | 6.8 | ||
Not clear | 1 primary outcome | 2 | 12.5 | 1 | 1.8 | 3 | 4.5 | 6 | 4.7 | 12 | 4.5 | |
2 + primary outcomes | 0 | 0.0 | 0 | 0.0 | 1 | 1.5 | 2 | 1.6 | 3 | 1.1 | ||
Allocation ratio | Equal e.g. 1:1 | 13 | 81.3 | 46 | 83.6 | 55 | 83.3 | 115 | 90.6 | 229 | 86.7 | |
Not equal e.g. 2:1 | 2 | 12.5 | 8 | 14.5 | 10 | 15.2 | 12 | 9.4 | 32 | 12.1 | ||
Not clear | 1 | 6.3 | 1 | 1.8 | 1 | 1.5 | 0 | 0.0 | 3 | 1.1 | ||
Unit of randomisation | Individual | 12 | 75.0 | 52 | 94.5 | 62 | 93.9 | 113 | 89.0 | 239 | 90.5 | |
GP practice | 0 | 0.0 | 0 | 0.0 | 1 | 1.5 | 9 | 7.1 | 10 | 3.8 | ||
Dyad (e.g. mother-child) | 1 | 6.3 | 1 | 1.8 | 1 | 1.5 | 2 | 1.6 | 5 | 1.9 | ||
Other | 3 | 18.8 | 2 | 3.6 | 2 | 3.0 | 3 | 2.4 | 10h | 3.8 | ||
Blinding | Yes, blinding | 11 | 68.8 | 37 | 67.3 | 45 | 68.2 | 69 | 54.3 | 162 | 61.4 | |
No, not blinded | Justification provided | 2 | 12.5 | 3 | 5.5 | 5 | 7.6 | 33 | 26.0 | 43i | 16.3 | |
Justification not provided | 1 | 6.3 | 9 | 16.4 | 15 | 22.7 | 10 | 7.9 | 35 | 13.3 | ||
Not clear | 2 | 12.5 | 6 | 10.9 | 1 | 1.5 | 15 | 11.8 | 24 | 9.1 |