Bench-to-bedside review: The evaluation of complex interventions in critical care

Anthony Delaney¹ , Derek C Angus² , Rinaldo Bellomo³ , Peter Cameron⁴ , D James Cooper⁵ , Simon Finfer⁶ , David A Harrison⁷ , David T Huang² , John A Myburgh⁸ , Sandra L Peake⁹ , Michael C Reade¹⁰ , Steve AR Webb¹¹ and Donald M Yealy¹² for the Australian Resuscitation in Sepsis Evaluation (ARISE), Protocolized Care for Early Septic Shock (ProCESS) and Protocolised Management In Sepsis (ProMISe) investigators

¹Northern Clinical School, Faculty of Medicine, University of Sydney, Intensive Care Unit, Royal North Shore Hospital, Pacific Highway, St Leonards, NSW, 2065, Australia

²Department of Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA

³Department of Intensive Care, Austin Hospital, Heidelberg, Victoria, Australia

⁴Department of Epidemiology and Preventive Medicine, Monash University and Alfred Hospital, Melbourne, Australia

⁵Department of Intensive Care Medicine, Monash University and Alfred Hospital, Melbourne, Australia

⁶Royal North Shore Hospital of Sydney, Sydney, Australia

⁷ICNARC, Tavistock House, Tavistock Square, London, UK

⁸Department of Intensive Care Medicine, The St George Hospital, Sydney, New South Wales, Australia

⁹Department of Intensive Care Medicine, Queen Elizabeth Hospital, Adelaide, SA, Australia

¹⁰Austin Hospital, University of Melbourne, Melbourne, Victoria, Australia

¹¹Royal Perth Hospital, University of Western Australia, Perth, Western Australia

¹²Department of Emergency Medicine, University of Pittsburgh, Pittsburgh, PA, USA

author email corresponding author email

Critical Care 2008, 12:210doi:10.1186/cc6849


Published:	14 April 2008

Abstract

Complex interventions, such as the introduction of medical emergency teams or an early goal-directed therapy protocol, are developed from a number of components that may act both independently and inter-dependently. There is an emerging body of literature advocating the use of integrated complex interventions to optimise the treatment of critically ill patients. As with any other treatment, complex interventions should undergo careful evaluation prior to widespread introduction into clinical practice. During the development of an international collaboration of researchers investigating protocol-based approaches to the resuscitation of patients with severe sepsis, we examined the specific issues related to the evaluation of complex interventions. This review outlines some of these issues. The issues specific to trials of complex interventions that require particular attention include determining an appropriate study population and defining current treatments and outcomes in that population, defining the study intervention and the treatment to be used in the control group, and deploying the intervention in a standardised manner. The context in which the research takes place, including existing staffing levels and existing protocols and procedures, is crucial. We also discuss specific details of trial execution, in particular randomization, blinded outcome adjudication and analysis of the results, which are key to avoiding bias in the design and interpretation of such trials.

These aspects of study design impact upon the evaluation of complex interventions in critical care. Clinicians should also consider these specific issues when implementing new complex interventions into their practice.