Everything you always wanted to know about EBN but were afraid to ask… Carl Thompson and Nicky Cullum Centre for Evidence Based Nursing, University of.

Everything you always wanted to know about EBN

but were afraid to ask…

Carl Thompson and Nicky CullumCentre for Evidence Based

Nursing, University of York

Aims

•To introduce you to key principles and processes of evidence based nursing including strategies and resouces to promote evidence based care

Clinical ScenarioYou are a senior nurse on an

acute admissions ward where lumbar punctures are regularly undertaken for diagnostic purposes. Standard practice has long been to lie people flat to reduce the likelihood of headache but the Unit Manager asks if this period of bedrest can be reduced or abolished as this bed-blocking is giving her a headache…

Please write on the pink paper how long you think

someone should lie flat after lumbar puncture (please

make it clear whether your answer is in minutes or

hours)

Where do we go for help with decisions when we are not sure how to proceed?

Good Idea or Bad Idea?• A weekly exercise programme for

nursing staff in the workplace• Bicycle safety education

programmes for children• Driver education for teenagers• Pint glasses made of toughened

glass for use in pubs• Lying babies prone to prevent

choking

Good Idea or Bad Idea??

• Weekly exercise programme for nursing staff had no effect on fitness and health, merely interfered with ability to plan work

• Bicycle safety education programme for children increased risk of injury overall, doubling risk in boys

• Teenage driver education associated with a modest but potentially important increase in teenagers involved in traffic crashes

• Use of toughened pint glasses in bars increased injury rate by 60% because the glass shattered more easily

• Lying babies prone for sleep intuitively makes sense (reduction of risk of inhaling vomit or choking), but increases risk of sudden infant death syndrome

We may inadvertently widen health inequalities …

• Bike Ed cycle safety programme was more harmful in younger children, those from families with lower parental education levels, those in families without other cyclists

• Sesame Street benefited all children but gap between fast and slow learners increased

Evidence based

decision

Evidence from research

Patient Preferences

Available resources

Professional expertise

REFLECT ON PRACTICE; IDENTIFY AREAS OF UNCERTAINTY

PHRASE ANSWERABLE QUESTIONS

SEARCH FOR RESEARCH EVIDENCE

CRITICAL APPRAISAL OF THE RESEARCH

IMPLEMENTATION WHERE APPROPRIATE

AUDIT

Nursing Uncertainty• Diagnosis• Selecting interventions

– targeting– timing

• Organising Care• Communication (including communication

of risks and benefits)• The patient experience• Prognosis• Health Needs Assessment

Question formation - PICO

• Population (who are the relevant people?)

• Interventions or exposures (diagnostic tests, foods, drugs, environmental hazards etc)

• Control or Alternative intervention/exposure

• Outcome (what are the person-level consequences we are interested in?)

Population

Who are the relevant people?

Intervention

What are they exposed to?

Alternative or control intervention

Outcome (what are the person-level consequences we are interested in?)

Focusing Answerable Questions

Population Intervention or Exposure

Alternative Intervention or Exposure

Outcomes

Scenarios• Focus these

uncertainties into answerable questions

Falls Prevention

• You are working in a PCT and a GP rings to say she is developing a practice protocol on preventing falls in older people. She asks you what should go into the protocol.

Focusing Answerable Questions

Population Intervention or Exposure

Alternative Intervention or Exposure

Outcomes

Exercise on Prescription

•You are working in a PCT and your Chief Executive decides that local practices should run an exercise on prescription scheme – how would you respond?

Focusing Answerable Questions

Population Intervention or Exposure

Alternative Intervention or Exposure

Outcomes

Mammography

A 40 year old friend with no symptoms or family history, has registered with a new GP who suggested that she have her first mammogram. Your friend asks you your opinion as to whether this is worthwhile?

Focusing Answerable Questions

Population Intervention or Exposure

Alternative Intervention or Exposure

Outcomes

REFLECT ON PRACTICE; IDENTIFY AREAS OF UNCERTAINTY

PHRASE ANSWERABLE QUESTIONS

SEARCH FOR RESEARCH EVIDENCE

CRITICAL APPRAISAL OF THE RESEARCH

IMPLEMENTATION WHERE APPROPRIATE

AUDIT

Fundamental Principle of Evidence Based anything…• The weight given to research evidence for

any decision depends on internal validity and relevance (external validity) of research

• Match the type of question with the best research design– Certain research designs likely to yield

more valid (more likely true) results for particular types of questions (minimise bias)

Matching questions to designsType of Question

Best Design

Intervention incl. prevention

RCT

Screening RCT

Diagnostic test Independent comparison with gold standard

Harm RCT; cohort

Aetiology Prospective cohort

Describing phenomena

Qualitative

Why are randomised controlled trials the best design for answering questions of effectiveness?

• Only when the treatment under evaluation is the only systematic difference between the groups in a trial can we confidently attribute a difference in outcomes to the treatment

Randomised controlled trial

Eligible patients

Experimental intervention

Control intervention

OUTCOME

NO OUTCOME

OUTCOME

NO OUTCOME

Direction of data collection: exposure outcome

Poor quality and/or irrelevant research

The total body of research is distilled down to a conclusion based on the best available, reliable and relevant research

Systematic reviews

• Reviews that look, in a systematic way, at all the available research on a topic

• Systematic reviews have a clear method - like original research

• Critically appraise each piece of research they include

• Reliable information for practice

Examples of Systematic Reviews from the Cochrane Library• Beds, mattresses and cushions for

preventing pressure ulcers• Non-nutritive sucking for pre-term infants• Absorbent products for containing urinary

and/or faecal incontinence in adults

• Caregiver support for women during childbirth

• Communiciating with children and adolescents about their cancer

REFLECT ON PRACTICE; IDENTIFY AREAS OF UNCERTAINTY

PHRASE ANSWERABLE QUESTIONS

SEARCH FOR RESEARCH EVIDENCE

CRITICAL APPRAISAL OF THE RESEARCH

IMPLEMENTATION WHERE APPROPRIATE

AUDIT

Take Home MessageWhere most research belongs

Only approximately 10% of articles in the most prestigious internal medicine journals can be regarded as “valid” and ready for application

Critical Appraisal

• Important for practitioners to be able to sort the good research from the bad quickly

• A number of checklists available; different ones for different research designs

• See Evidence Based Nursing Users’ Guides

• CASP website http://www.phru.org.uk/~casp/appraisa.htm

Features of Clinically Useful Information

•Trustworthy (pre-appraised)•Concise•Easy to understand•Easy to access•Clear implications for

practice

Sources of Pre-Appraised Research

• Clinical Evidence • Evidence Based journals

– Evidence Based Nursing, Medicine, Mental Health etc

• Systematic reviews– Cochrane Library (via NeLH)

•Cochrane Database of Systematic Reviews

•DARE - Database of Abstracts of Reviews of Effectiveness

Evidence Based journals

• Aim to select, from international literature, best quality research and reviews relevant to medicine, nursing etc

• Summarises each article in “value-added” abstracts

• Commentary from clinical expert

Sources of Clinically Useful Information

• SYSTEMS – decision support – brings research directly into clinical decision making

• SYNOPSES – eg. Clinical Evidence, evidence based journals, DARE database, précis and appraisal element

• SYNTHESES – systematic reviews of all relevant primary research (Cochrane Library) (primary research pre-appraised_

• STUDIES – MEDLINE, Cinahl, etc.

Haynes’s Typology of Research Information (4S)

syntheses

synopses

Systems

Synopses

Syntheses (reviews)

Studies

Search For A Relevant Synopsis Of (or Including) A Valid, Up to Date Systematic Review (eg, Evidence Based journals, Clinical Evidence)

Search The Cochrane Library For A Valid, Up to Date Systematic Review

Search for a Synopsis of Primary Research eg, RCTs (Evidence Based journals, Clinical Evidence)

Search MEDLINE, CINAHL, Cochrane Library (Cochrane Controlled Trials Register) for primary research

No?

No?

Whatever you find, remember to appraise for validity! Use of Checklist!

No?

Focusing Answerable Questions

Population Intervention or Exposure

Alternative Intervention or Exposure

Outcomes

Women over 40

Mammo-graphy screening

No Mammo-graphy

Mortality

Focusing Answerable Questions

Population Intervention or Exposure

Alternative Intervention or Exposure

Outcomes

People aged over 70 years

Fall prevention strategies eg. exercise

No fall prevention or alternative

Fracture rates

Focusing Answerable Questions

Population Intervention or Exposure

Alternative Intervention or Exposure

Outcomes

People with CHD

Exercise on prescrip-tion

No exercise on script

Coronary events

REFLECT ON PRACTICE; IDENTIFY AREAS OF UNCERTAINTY

PHRASE ANSWERABLE QUESTIONS

SEARCH FOR RESEARCH EVIDENCE

CRITICAL APPRAISAL OF THE RESEARCH

IMPLEMENTATION WHERE APPROPRIATE

AUDIT

Where do you start?

• Work with nurse colleagues to identify common clinical uncertainties

• Frame these as answerable, searchable questions

• Search for answers following the synopsis, synthesis, study approach

Back to Lumbar Puncture

Question would be?

Question would be

In patients having cervical or lumbar puncture, is longer bed rest more effective than immediate mobilisation or short bed rest in preventing headache?

Search For A Synopsis Of A Valid, Up to Date Systematic Review (eg, Evidence Based journals, Clinical Evidence)

Search The Cochrane Library For A Valid, Up to Date Systematic Review

Search for a Synopsis of Primary Research eg, RCTs (Evidence Based journals, Clinical Evidence)

Search MEDLINE, CINAHL, Cochrane Library (Cochrane Controlled Trials Register) for primary research

No?

No?

Whatever you find, remember to appraise for validity! Use of Checklist!

No?

“However, there is really no good evidence that routine bed rest after dural puncture is beneficial, whatever the reason for the procedure, and the available data suggest that it may even increase the risk of postural headache…

…Hence, while there is clearly a role for bed rest for the relief of the symptoms of established post-dural puncture headache, the results of this review indicate that routine bed rest should be abandoned, and that patients should be encouraged to mobilise freely after dural puncture as soon as they are able.”

Sudlow and Warlow, Cochrane Review first published 2002.

Are You Convinced By This Evidence?

Please write on the orange paper what duration of bedrest you

would now advocate after lumbar puncture

Email survey of teaching staff in our department

“Royal Marsden Manual (2000) suggests 4 hours if there is no headache. If there is then they should continue to lie flat and be observed for signs of alteration in intracranial pressure. In this case they can presumably sit up in the absence of any signs and once headchae reolved”

“I think its around four to six hours but varies between hospitals up to 12 hours”.

“They should lie flat in a comfortable position for up to 90 minutes after the test, this will depend upon how traumatic the tap was, age, BP etc'. The aim is to allow the CSF circualtion to re-establish itself and prevent a low pressure headache.”