The I-STRAT trial: Do Isolation Strategies reduce endemic levels of MRSA and Clostridium difficle associated diarrhoea

Lead Research Organisation: University College London
Department Name: Unlisted


What do most people fear about coming into hospital? Catching a superbug infection such as MRSA or Clostridium difficile! Despite a tranche of Government initiatives to reduce these, they appear rampant. Surely their control should be simple. Keep the hospitals clean! Make sure staff clean their hands! Put people with these infections into isolation straight away! However, it is this last intervention , isolation, that proves so difficult.

Infection Control staff often bemoan the lack of effective isolation facilities. Managers say they cannot afford to make more isolation beds available, especially as there is no good evidence from a proper trial to prove this works. This study will get to the bottom of the difficulties in providing effective isolation. It will help Trusts, through a nationwide consultation, and intensive work with 25-30 trusts, to work out the barriers, at organizational and individual levels, to effective isolation. It will help them come up with ideas of how to make isolation facilities available and make the most of those facilities that they have. Trusts will be able to design the isolation policies they think most likely to work, a small number will ?test drive? these in a preliminary trial that can then be rolled out to a larger number of hospitals, to find the best way to reduce MRSA and Clostridium difficile through isolation.

The two lead researchers in the I-STRAT trial, Barry Cookson and Sheldon Stone, say ?Nowhere in the world has looked at how best to make isolation work. Part of the reason for that is that there are so many difficulties in running a proper trial of this. People think that isolation may be expensive, or that is it hard to provide designated staff. No one is even sure exactly which patients should be isolated, or how we should measure success. This study is going to address these issues, working closely with Trusts, to help them come up with their own interventions to design a feasible ?mini-trial?. If that looks practical, then we could move to a full scale trial which might provide us with some definite answers about the role of isolation in fighting these so-called ?superbugs?

Technical Summary

MRSA and CDAD continue to be endemic in the NHS despite widespread use of side room and cohort isolation of patients and intensive nationwide efforts to improve hand-hygiene (cleanyourhands campaign), hospital cleanliness (Cleaner Hospitals) and embed infection control in clinical governance (Saving Lives, Safer Patients Initiative, Health Act). Direct staff/patient contact transmits both infections. Patient Isolation (in isolation wards, side rooms or cohorts on general wards with/without cohorting of nursing staff) remains an important cornerstone of management. The biological plausibility of isolation as a control measure is supported by epidemiological modelling but not by RCTs, and its effectiveness has been questioned. Better quality infection control research is needed to inform policy and practice. There are many barriers to performing such research on isolation strategies making it difficult to design theoretically grounded, affordable and pragmatic trials. These include ethical, financial, resource utilisation, organisational and behavioural barriers at institutional, ward and healthcare worker (HCW) levels none of which have been clearly defined. There is also a lack of consensus regarding target patient population or common outcome data to inform power calculations, constant contextual changes in infection control practice and an absence of process measures to understand the extent of and influences on implementation of interventions.

We are a suitably experienced multidisciplinary team, wishing to design a stepped-wedge Cluster Randomized Controlled Trial, possibly a preference trial, of one or more isolation strategies to reduce CDAD and MRSA, in settings where these infections are common and other infection control practice is maximal. We will scope interest in the trial from acute Trusts, identify the barriers to different interventions at institutional, ward and Healthcare worker (HCW) levels, seek ways of addressing these, establish Trusts? preferred intervention(s) and target population(s), identify components of intervention(s), explore ethical issues with Trusts and patient groups, undertake an exploratory trial to establish a pragmatic intervention, and provide common outcome measures for power calculations to size the definitive effectiveness and cost-effectiveness trial. Our experience of running a stepped-wedge CRCT to improve hand-hygiene , a crossover study of side room isolation and developing the ORION statement, a CONSORT equivalent for infection control studies, has informed our approach that a high quality CRCT should draw on the MRC framework for complex interventions, the ORION statement, the European consensus health framework for using psychological theory to assess explanations for, and change, HCW practice and measure fidelity to intervention to provide information about mediation.


10 25 50
Description PAC report
Geographic Reach National 
Policy Influence Type Gave evidence to a government review
Description Parliamentary Accounts Committee
Geographic Reach National 
Policy Influence Type Gave evidence to a government review
Description Policy Research Programme
Amount £267,733 (GBP)
Funding ID 019/0050 
Organisation Department of Health Social Services and Public Safety (DHSSPS) 
Sector Public
Country United Kingdom
Start 12/2010 
End 11/2013
Title I STRAT site visits 
Description Data base of views of infection control teams ward managers and bed managers on isoaltion and new strategies 
Type Of Material Improvements to research infrastructure 
Provided To Others? No  
Impact None at present 
Title adoption of new temporary isolation screens developed by NHS Innovations and of admission and discharge screening as an outcome measure for MRSA intervention trials 
Description Easy to erect screens that separate patients and provide a temporary isoaltion barrier. 
Type Of Material Improvements to research infrastructure 
Provided To Others? No  
Impact None 
Description National Audit Office -I-Strat collaboration 
Organisation National Audit Office
Country United Kingdom 
Sector Public 
PI Contribution Team created questionns for NAO national mandatory survey on infection control regarding Isolation, Hand hygiene, antibiotic management, screening and piloteed emtrire questionnaire to chief executives, DIPCs and ICTs
Collaborator Contribution Quality control of our data. Facilitation of the second phase of the MRC funded ISTRAT study
Impact Report from NOA which has gone to Palriamentray Accounts Committee. This has recommended urgent evaluation of national MRSA screening efforts and we have been asked to put a full proposal to the DoH for funding. We are also in discussion about studying the relationship between infection control interventions and proactices detaield in the NAO report and levels of HCAI.
Start Year 2008
Description National Focus meeting 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? No
Primary Audience Health professionals
Results and Impact 30 infection control health care professionlals and representatives of lay organisations participated in a workshop disseminating the results of hospital visits and interveiews on isoaltion practices and preferences.

This lead to a conocensus agrement on prefered isolation stratgeis to test out, and to agreement on outcome measures (eg MRSA discharge screens) acceptable to patients and staff
Year(s) Of Engagement Activity 2010
Description Publication NAO report 
Form Of Engagement Activity A magazine, newsletter or online publication
Part Of Official Scheme? Yes
Primary Audience Policymakers/politicians
Results and Impact NAO report publsihed on line and released to all hospitals. Report to Parliamentary Accounts committee who responded in Novemeber 2009

PAC urgently wanted study of implementation, effectiveness and cost-effectiveness of national MRSA screening programme. We entered into discussions with DoH who asked us to submit a formal proposal to study this. They are currently making a business case to fund it.
Year(s) Of Engagement Activity 2008,2009