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Research Article| Volume 41, SUPPLEMENT 1, S20-S23, July 2010

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Challenging issues in randomised controlled trials

  • A.D. Nichol
    Correspondence
    Corresponding author at: Australian and New Zealand Intensive Care Research Centre, School of Public Health and Preventive Medicine, Monash University, Alfred Hospital Campus, 89 Commercial Road, Melbourne 3004, Australia. Tel.: +61 3 99030247; fax: +61 3 99030071.
    Affiliations
    Australian and New Zealand Intensive Care - Research Centre (ANZIC-RC), Monash University, Melbourne, Victoria 3004, Australia

    Alfred Hospital, Melbourne, Victoria 3004, Australia
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  • M. Bailey
    Affiliations
    Australian and New Zealand Intensive Care - Research Centre (ANZIC-RC), Monash University, Melbourne, Victoria 3004, Australia
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  • D.J. Cooper
    Affiliations
    Australian and New Zealand Intensive Care - Research Centre (ANZIC-RC), Monash University, Melbourne, Victoria 3004, Australia

    Alfred Hospital, Melbourne, Victoria 3004, Australia
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  • On behalf of the POLAR and EPO investigators
    Author Footnotes
    1 The POLAR Study investigators: D James Cooper, Stephen Bernard, Alistair Nichol, John Myburgh, Jeffery Presneil, Peter Cameron, Andrew Forbes, Lynne Murray, Jeffery Rosenfeld. The EPO-TBI Study investigators: Rinaldo Bellomo, D James Cooper, Alison Street, Alistair Nichol, Craig French, Jeffery Presneil, John McNeil, Neil Orford, Jeffery Rosenfeld, Gillian Syres, Michael Bailey, Ann Mak, Shirley Vallance, Lorraine Little.
  • Author Footnotes
    1 The POLAR Study investigators: D James Cooper, Stephen Bernard, Alistair Nichol, John Myburgh, Jeffery Presneil, Peter Cameron, Andrew Forbes, Lynne Murray, Jeffery Rosenfeld. The EPO-TBI Study investigators: Rinaldo Bellomo, D James Cooper, Alison Street, Alistair Nichol, Craig French, Jeffery Presneil, John McNeil, Neil Orford, Jeffery Rosenfeld, Gillian Syres, Michael Bailey, Ann Mak, Shirley Vallance, Lorraine Little.

Abstract

What this topic is about

Randomised controlled trials (RCTs) are the most rigorous way of determining whether a cause–effect relation exists between treatment and outcome and are an integral component in the hierarchy of evidence which guide current clinical practice. Whether ensuring the success of a RCT or interpreting the medical literature, it is important to understand the key components of RCT design to assess their quality and therefore the weight which should be attributed to its findings. This article will highlight some of these key components by using a number of ongoing trauma studies being co-ordinated by the Australian and New Zealand Intensive Care Research Centre, Monash University.

Common problems and challenges

The quality of many RCTs could be improved by avoiding some common pitfalls, such as (i) unclear hypotheses and multiple objectives, (ii) poor selection of endpoints, (iii) inappropriate subject selection criteria, (iv) non-clinically relevant or feasible treatment/intervention regimens, (v) inadequate randomisation, stratification, blinding, (vi) lack of stratification in small RCTs (vii) inadequate blinding of trials, (viii) insufficient sample size/power, (ix) failure to use intention to treat analysis and (x) failure to anticipate common practical problems encountered during the conduct of a RCT.

Tips for researchers

The RCTs most likely to be funded and/or be of high quality always address these issues.

Keywords

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