THE NATURE OF EVIDENCE
Foundations in Evidence Based Practice
B71P02
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
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)
Definitions of EBP
‘Clinical decisions should […] be informed by up-todate, 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outdated primary training or over interpretation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.
Relevance of EBP to nursing
practice
What areas of nursing
practice might we want to
ask EBP questions about?
Discuss this with a
partner.
Relevance of EBP to nursing practice
You might ask questions about a range of categories of practice:
1.
Assessment – how to properly gather and interpret findings?
2.
Causes of the problem – how to identify them?
3.
Deciding what the problem is – where the symptoms/signs indicate a range of
possible problems how do you decide which is most likely?
4.
How to select and interpret tests used to identify problems and to monitor patient
progress?
5.
How to estimate the likely clinical progression of a condition/illness and any likely
complications?
6.
How to select interventions that do more good than harm and that are worth the
effort and cost of doing them?
7.
How to reduce the chance of the problem reoccurring or how to promote health?
8.
How to keep up to date; improve your skills; and run a more effective/efficient nursing
team?
9.
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)
WHY IS BEST EVIDENCE AND EVIDENCE BASED
NURSING IMPORTANT?
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?
 Ensures patient/clients receive the care that fits their
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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
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)
Evidence Classified by
Level:
¶ At least one systematic review of multiple, well designed
·
¸
¹
º
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)
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.
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
The Evidence Quiz
1. Evidence is important to nurses because:
a) It minimises the risks to patients
b) You don’t need to think about your actions
anymore because the evidence does that for you
c) It ensure that patients receive care based on
robust research
d) It ensures that research journals stay in business
The Evidence Quiz
2. Evidence may help to answer questions
about:
Methods of nursing assessment
b) What time the evening meal arrives on the ward
c) Whether it is tasteful for Mr James to wear a
thong on a mixed sex ward
d) How to select interventions that do more good
than harm
a)
The Evidence Quiz
3. Robust Evidence may be obtained from:
a)
b)
c)
d)
e)
f)
Google
Heat magazine
The Cochrane library
Wikipedia
CINAHL
Nursing Times
The Evidence Quiz
4. The strongest forms of evidence may be
obtained from:
The Times newspaper
b) Systematic Reviews
c) The bloke at the chippy
d) Randomised Controlled Trials (RCT’s)
a)
References
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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.