The Nature of Evidence

1. Foundations in Evidence Based Practice B71P02 The Nature of Evidence

2. Session Outcomes At the end of this session you will be able to: • Define Evidence Based Practice • Identify reasons for Promoting Evidence Based Practice • Identify nursing practice that might benefit from the use of evidence • Appreciate different forms of evidence

3. Definitions of EBP Sackett et al (1996) define EBP as ‘ the conscientious, explicit and judicious use of current best evidence in making nursing decisions about the care of individual patients’ Carnwell defines EBP as ‘[the] systematic search for, and appraisal of, best evidence in order to make clinical decisions that might require changes in current practice, while taking into account the individual needs of the patient.’ She adds: ‘Best evidence might be defined as that which is valid and relevant to the patient.’ (Carnwell, 2001)

4. Definitions of EBP ‘Clinical decisions should […] be informed by up-to-date, relevant and robust evidence rather than outdated primary training or over interpretation of individual patient experiences (Donald & Greenhalgh, 2000; Sackett et al, 2000) Use of best evidence is thus important.

5. Relevance of EBP to nursing practice What areas of nursing practice might we want to ask EBP questions about? Discuss this with a partner.

6. Relevance of EBP to nursing practice You might ask questions about a range of categories of practice: • Assessment – how to properly gather and interpret findings? • Causes of the problem – how to identify them? • Deciding what the problem is – where the symptoms/signs indicate a range of possible problems how do you decide which is most likely? • How to select and interpret tests used to identify problems and to monitor patient progress? • How to estimate the likely clinical progression of a condition/illness and any likely complications? • How to select interventions that do more good than harm and that are worth the effort and cost of doing them? • How to reduce the chance of the problem reoccurring or how to promote health? • How to keep up to date; improve your skills; and run a more effective/efficient nursing team? • How best to understand the perceptions of individuals and groups e.g. service users and carers Adapted from Sackett et al (1997) (http://www.mdx.ac.uk/www/rctsh/ebp/question.htm - Accessed 22/11/07)

7. With a partner make a list of reasons why we should use evidence to underpin nursing care Why is best evidence and evidence based nursing important?

8. Why is best evidence and evidence based nursing important? • Ensures patient/clients receive the care that fits their needs • Facilitates sound decision making and makes it more explicit • Minimises risk to the patient/client so that benefits outweigh harm • Provides the nurse with the skills and knowledge to evaluate healthcare literature and practice • Exposes gaps in knowledge and conflicts in evidence

9. What is Evidence? • In the context of evidence based practice this is research published in professional and academic journals and systematic reviews of research found in databases of evidence (such as Cochrane). • ‘ Knowledge derived from a variety of sources that has been found to be credible’ (Higgs & Jones 2000)

10. Evidence Classified by Level: • At least one systematic review of multiple, well designed randomised controlled trials (RCT’s) • At least one properly designed RCT of appropriate size • Well designed trials without randomisation, single group pre-post, cohort, or matched case controlled studies • Well designed, non-experimental studies from more than one centre or research group • Opinions of respected authorities, based on clinical evidence, descriptive studies or reports of expert committees (Source: Muir Gray, 1997)

11. Other Forms of Evidence • Evidence based on experiences (professional or personal) • Evidence gathered from patients/clients and/or carers. • Evidence based theory that is not research based. Le May (1999) ‘Evidence-based practice’ Nursing Times, Monographs, 1;2.

12. What EBP is not • EBP is not cook-book practice • evidence needs extrapolation to the patient’s unique biology and values • EBP is not cost-cutting practice • when efficacy for the patient is paramount, costs may rise, not fall

13. The Evidence Quiz • Evidence is important to nurses because: • It minimises the risks to patients • You don’t need to think about your actions anymore because the evidence does that for you • It ensure that patients receive care based on robust research • It ensures that research journals stay in business

14. The Evidence Quiz • Evidence may help to answer questions about: • Methods of nursing assessment • What time the evening meal arrives on the ward • Whether it is tasteful for Mr James to wear a thong on a mixed sex ward • How to select interventions that do more good than harm

15. The Evidence Quiz • Robust Evidence may be obtained from: • Google • Heat magazine • The Cochrane library • Wikipedia • CINAHL • Nursing Times

16. The Evidence Quiz • The strongest forms of evidence may be obtained from: • The Times newspaper • Systematic Reviews • The bloke at the chippy • Randomised Controlled Trials (RCT’s)

17. References • Carnwell, R. (2001) ‘Essential differences between research and evidence-based practice’, Nurse Researcher, Vol.8, No.2, pp.55-68. • DoH (1997) The New NHS: Modern, Dependable, London, The Stationary Office. • DoH (1999) Making a Difference: Strengthening the nursing, midwifery and health visiting contribution to health and healthcare, London, Department of Health. • Donald, A. and Greenhalgh, T. (2000) A Hands-on Guide to Evidence Based Healthcare: Practice and Implementation, Blackwell Science, Oxford. • Le May, A. (1999) Evidence-base practice, London, Nursing Times Books. • Muir Gray, J.A. (1997) Evidence-based Health Care. How to make Health Policy and Management Decisions, Edinburgh, Churchill Livingstone. • Sackett, D.L., Rosenberg, W.M., Gray, J.A., Haynes, R.B. and Richardson, W.S. (1996) ‘Evidence based medicine: What it is and what it isn’t’, British Medical Journal, 312, 7023, pp. 71-72. • Sackett, D.L., Strauss, S.E., Richardson, W.S., Rosenberg, W. and Haynes, R.B. (2000) Evidence Based Medicine: How to Practice and Teach EBM, 2nd edn, Edinburgh, Churchill Livingstone.