Intended for healthcare professionals

Education And Debate

Need for expertise based randomised controlled trials

BMJ 2005; 330 doi: (Published 06 January 2005) Cite this as: BMJ 2005;330:88
  1. P J Devereaux, assistant professor (,
  2. Mohit Bhandari, orthopaedic surgeon2,
  3. Mike Clarke, director3,
  4. Victor M Montori, assistant professor4,
  5. Deborah J Cook, professor1,
  6. Salim Yusuf, professor5,
  7. David L Sackett, director6,
  8. Claudio S Cinà, vascular surgeon2,
  9. S D Walter, professor1,
  10. Brian Haynes, professor1,
  11. Holger J Schünemann, associate professor7,
  12. Geoffrey R Norman, professor1,
  13. Gordon H Guyatt, professor1
  1. 1 Department of Clinical Epidemiology and Biostatistics, McMaster University, 1200 Main Street, West Hamilton ON, Canada L8N 3Z5,
  2. 2 Department of Surgery, McMaster University,
  3. 3 UK Cochrane Centre, Oxford,
  4. 4 Department of Medicine, Mayo Clinic College of Medicine, Rochester, Minnesota, United States,
  5. 5 Population Health Research Institute, McMaster University,
  6. 6 Trout Research and Education Centre of Irish Lake, Markdale, Ontario, Canada,
  7. 7 Departments of Medicine and Social and Preventive Medicine, University at Buffalo, Buffalo, New York, United States
  1. Correspondence to: P J Devereaux
  • Accepted 24 October 2004

Surgical procedures are less likely to be rigorously evidence based than drug treatments because of difficulties with randomisation. Expertise based trials could be the way forward


Although conventional randomised controlled trials are widely recognised as the most reliable method to evaluate pharmacological interventions,1 2 scepticism about their role in nonpharmacological interventions (such as surgery) remains.36 Conventional randomised controlled trials typically randomise participants to one of two intervenions (A or B) and individual clinicians give intervention A to some participants and B to others. An alternative trial design, the expertise based randomised controlled trial, randomises participants to clinicians with expertise in intervention A or clinicians with expertise in intervention B, and the clinicians perform only the procedure they are expert in. We present evidence to support our argument that increased use of the expertise based design will enhance the validity, applicability, feasibility, and ethical integrity of randomised controlled trials in surgery, as well as in other areas. We focus on established surgical interventions rather than new surgical procedures in which clinicians have not established expertise.

Use of expertise based trials

Investigators have used the expertise based design when conventional randomised controlled trials were impossible because different specialty groups provided the interventions under evaluation—for example, percutaneous transluminal coronary angioplasty versus coronary artery bypass graft surgery.79 In 1980, Van der Linden suggested randomising participants to clinicians committed to performing different interventions in an area in which a conventional randomised controlled trial was possible.10 Since that time, however, the expertise based design has been little used, even in areas where it has high potential (such as, surgery, physiotherapy, and chiropractic).

Problems with validity of conventional randomised controlled trials

Differential expertise between procedures

Because it takes training and experience to develop expertise in surgical interventions, individual surgeons tend to solely or primarily use a single surgical approach to treat a specific problem.10 11 …

View Full Text

Log in

Log in through your institution


* For online subscription