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Table 2 Trial demographics by journal

From: A cohort examination to establish reporting of the remit and function of Trial Steering Committees in randomised controlled trials

  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
  1. BMJ British Medical Journal, HTA Health Technology Assessment Monograph series, NEJM New England Journal of Medicine
  2. aAdvertisements in newsletters (n = 1); Child and Adolescent Mental Health Services (n = 1); Community mental health teams (n = 1); Community nurse services (n = 1); Community nursing services and community leg ulcers clinics (n = 1); Community old age psychiatry services (n = 1); Community sources (n = 1); Department of Veterans Affairs (n = 3); National population registrar (n = 1); Community paediatricians (n = 1); Registrar (n = 3); Schools (n = 1); Secondary schools (n = 1); University podiatry schools and podiatry clinics (n = 1); Vaccination centres in schools (n = 1); Villages (n = 1); Not specified (n = 8)
  3. bOther setting: Veterans Affairs Medical Centre (n = 1); From other trials (n = 1)
  4. cNot clear: Adult mental health setting (n = 1); Antenatal clinic (n = 1); Centres (n = 29); Child and Adolescent Mental Health Services (n = 1); Child Development Centre (n = 1); Clinic site (n = 1); Clinical centres (n = 1); Clinical sites (n = 1), Clinics (n = 2); Countries (n = 2); European medical centres (n = 1); Institutes (n = 1); Institutions (n = 1); Sites (n = 13); Not described (n = 7)
  5. dTotal arms equal to: six (n = 2); eight (n = 1); nine (n = 1); twelve (n = 1)
  6. eDefined by UK Clinical Research Collaboration Health Research Classification System
  7. fCategories not mutually exclusive
  8. gBoth: Composite (n = 3) (Disease improvement calculated from CHAQ, physician’ global assessment of disease activity, parents’ global assessment of overall well-being, number of joints with limited range of movement (ROM), number of active joints and erythrocyte sedimentation rate (n = 1)); Foot and Ankle Outcome Score (n = 1); Post-operative nausea and vomiting (n = 1)
  9. hOther units of randomisation: Clinic (n = 1); Family (n = 2); Hospital (n = 1); Household (n = 1); Partner (n = 1); School (n = 1); Village (n = 1); Year group (n = 1); Paediatric diabetes services (n = 1)
  10. iJustification for no blinding: Not possible or practical due to nature of intervention or trial design (n = 30); Not possible/practical as in practice caused difficulties for patients (n = 1); Not possible/practical as shown by other similar trials (n = 2); Not possible/practical so cluster randomisation approach used (n = 1); Not possible – no additional justification given (n = 4); Attempted to blind although were not successful (n = 1); Large sample size means that results are not compromise (n = 1); Not blinding reflects real practice (n = 2); Test for impact of not blinding post trial (n = 1)