This article explains the background to the epic2 revised national evidence-based guidelines for preventing healthcare-associated infections (known as epic2) (Pratt et al, 2007) and their development.
Over the past two decades, HCAIs have become a significant threat to patient safety. Technological advances in healthcare are often undermined by the transmission of infections, particularly those caused by antimicrobial-resistant strains of disease-causing micro-organisms that are now endemic in many healthcare environments.
Although not all HCAIs can be prevented, many can. Clinical effectiveness – using prevention measures based on reliable evidence of efficacy – is a core component of an effective strategy designed to protect patients from infection.
The original epic guidelines (Pratt et al, 2001) were systematically developed principles of good practice for preventing healthcare-associated infections (HCAIs) in NHS hospitals and other acute care health services. They were commissioned by the Department of Health (DH) and developed by a nurse-led multi-professional team at the Richard Wells Research Centre, ThamesValleyUniversity in consultation with key stakeholders, including royal colleges and professional and patient organisations.
The guidelines were part of the ‘epic initiative’ (evidence-based practice in infection control), intended to provide reliable best evidence for the development of local infection prevention and control guidelines and protocols that facilitate clinically effective practice. A complementary set of epic guidelines focus on preventing HCAIs in primary and community care (Pellowe et al, 2003).
Evidence reviews in 2004 and 2005 (Pellowe et al, 2004; 2005) indicated that some of the original epic guideline recommendations should be updated to ensure they:
- Continued to reflect new and emerging evidence;
- Remained relevant to infection control and prevention practice;
- Enjoyed the confidence of practitioners and patients.
These reviews led to the development of the epic2 guidelines, which now replace the original guidelines.
The guidelines consist of:
- Standard infection control principles, including hospital environmental hygiene, hand hygiene, use of personal protective equipment, and use and disposal of sharps;
- Preventing infections associated with the use of short-term indwelling urethral catheters;
- Preventing infections associated with the use of central venous access devices.
The evidence for the guidelines was identified by systematic reviews of experimental and non-experimental research. Evidence from expert opinion reflected in systematically identified professional, national and international guidelines was considered following formal assessment using a validated appraisal process (Agree Collaboration, 2001; SIGN, 2001). All evidence was critically appraised and the best available evidence influenced the guideline recommendations.
These guidelines can be adapted and used by all hospital practitioners. They will inform the development of detailed local protocols and ensure that important standard principles for infection prevention are incorporated. Consequently, they are aimed at hospital managers, members of hospital infection control teams, and individual health care practitioners. At an individual level, the guidelines are intended to influence the quality and effectiveness of infection prevention decision-making. Their dissemination also helps patients understand standard infection prevention precautions.
Each set of guidelines consists of:
- A resume of the systematic review process;
- A synthesis of the related evidence;
- An economic opinion, where appropriate;
- Guideline recommendation(s);
- A bibliography listing the cited evidence;
- Areas for further research and suggested audit criteria.
The evidence base will be reviewed in 2009 and it is planned that the guidelines will be updated in 2011.
In addition to informing local protocols, epic2 can be used as a benchmark for determining appropriate infection prevention decisions and, as part of reflective practice, to assess clinical effectiveness. They also provide a baseline for clinical audit, evaluation and education, and facilitate ongoing quality improvements.
It is not anticipated that implementing the guidelines will result in significant additional costs, unless additional equipment or resources are needed or where adherence to current guidance is poor.
Identifying evidence for appraisal
The guidelines were developed using a systematic reviews. Electronic databases were searched for national and international guidelines and research studies published between 1 January 1999 and 31 August 2005. A two-stage search process was used.
Stage 1: Identification of systematic reviews and guidelines
For each set of guidelines, an electronic search was conducted for systematic reviews of randomised controlled trials and current national and international guidelines in English. The following databases were searched:
- Cochrane Library;
- National Guideline Clearinghouse;
- National Electronic Library of Health;
- National Institute for Health and Clinical Excellence.
Guidelines were then critically appraised using the AGREE (2001) Instrument, an evaluation method for assessing the methodological quality of clinical practice guidelines. Accepted guidelines were included as part of the evidence base supporting the development of the epic guidelines. They were also used to verify professional consensus and in some instances, as the primary source of evidence.
Stage 2: Systematic search for additional evidence
Review questions for the systematic reviews of the literature were then developed for each set of epic guidelines following recommendations from expert advisors. On completion of the main search, an economic filter was applied. The following databases were searched:
- Cumulated Index of Nursing and Allied Health Literature;
- The Cochrane Library.
Titles and abstracts were printed for preliminary review, and the full text of those where the title or abstract:
- Addressed one or more of the review questions;
- Identified primary research or systematically conducted secondary research and/or;
- Indicated a theoretical, clinical or in-use study. Wherever possible, in-use rather than in vitro studies were retrieved.
All full-text studies retrieved were independently assessed by two experienced reviewers, who identified those meeting the inclusion criteria for critical appraisal.
Quality assessment and data extraction
Included studies were appraised using a process adapted from the study quality assessment system developed by the Scottish Intercollegiate Guideline Network (SIGN, 2001). All were appraised and data extracted by one experienced reviewer and checked by a second. Any disagreement between reviewers was resolved through discussion. Evidence tables were constructed from the quality assessments and the studies summarised in the evidence reports. The evidence was graded using methods adapted from SIGN (2001) by the National Institute for Health and Clinical Excellence (NICE, 2004; Harbour and Miller, 2001), as shown in Table 1.
Table 1. Levels of evidence for intervention studies
Level of evidence
Type of evidence
High-quality meta-analyses, systematic reviews of randomised controlled trials (RCT), or RCT with a very low risk of bias
Well-conducted meta-analyses, systematic reviews of RCT, or RCT with a low risk of bias
Meta-analyses, systematic reviews of RCT, or RCT with a high risk of bias*
High-quality systematic reviews of case–control or cohort studies
High-quality case–control or cohort studies with a very low risk of confounding, bias or chance and a high probability that the relationship is causal
Well-conducted case–control or cohort studies with a low risk of confounding, bias or chance and a moderate probability that the relationship is causal
Case–control or cohort studies with a high risk of confounding bias, or chance and a significant risk that the relationship is not causal*
Non-analytic studies (for example, case reports, case series)
Expert opinion, formal consensus
*Studies with a level of evidence ‘–‘ should not be used as a basis for making a recommendation
The evidence tables and reports were presented to the advisors for discussion. Expert advice derived from seminal works and appraised national and international guidelines were also considered. Following extensive discussion the guidelines were drafted. Factors influencing their recommendations included:
- The nature of the evidence;
- The applicability of the evidence;
- Costs and knowledge of healthcare systems.
The grading scheme adapted by NICE (2004) from SIGN (2001) was used to define the strength of recommendation (Table 2).
Table 2. Classification of recommendations
1. A good practice point (GPP) is a recommendation for best practice based on the experience of the Guideline Development Group
2. Recommendation from NICE Interventional Procedures guidance
The draft guidelines were circulated to a range of professional and public stakeholders for comment. All comments were collated for consideration by the guideline developers and advisors who agreed any changes to the draft recommendations.
Agree Collaboration (2001) Appraisal of Guidelines for Research and Evaluation Instrument. June 2001. www.agreecollaboration.org.
Harbour, R., Miller, J.A. (2001) A new system for grading recommendations in evidence based guidelines. British Medical Journal; 323: 7308, 334-336.
National Institute for Health and Clinical Excellence (2004) Guideline Development Methods: Information for National Collaborating Centres and Guideline Developers. www.nice.org.uk.
Pellowe, C.M. et al (2003) Infection Control: Prevention of healthcare-associated infection in primary and community care. Simultaneously published in: Journal of Hospital Infection; 55 (Supplement 2): 1-127 and British Journal of Infection Control; (Supplement) 4: 6, 1-100.
Pellowe, C.M. et al (2004) The epic project. Updating the evidence-base for national evidence-based guidelines for preventing healthcare-associated infections in NHS hospitals in England. British Journal of Infection Control; 5: 6, 10-15.
Pellowe, C.M. et al (2005) The epic project. Updating the evidence-base for national evidence-based guidelines for preventing healthcare-associated infections in NHS hospitals in England. [Letter]. Journal of Hospital Infection; 59: 4, 373-374.
Pratt, R.J. et al (2001) The epic project: developing national evidence-based guidelines for preventing healthcare associated infections. phase 1: guidelines for preventing hospital-acquired infections. Journal of Hospital Infection; 47 (Supplement): S1-S-82.
Scottish Intercollegiate Guideline Network (2001) A Guideline Developers' Handbook (SIGN 50). Available at: www.sign.ac.uk.