Critical Appraisal : The Librarian’s Role

Andrew Booth and Louise Falzon

What is critical appraisal?Weighing up evidence to assess:

• its validity (closeness to the truth)• its usefulness (clinical

applicability).Sackett and Haynes, 1995

FIND APPRAISE ACT

Can librarians get involved?

• Resource provider• Evidence locator• Appraiser• Digest Producer• Appraisal Tutor

Some familiar roles

• Resource provider– Critical appraisal tools– Critically appraised resources

• Evidence locator– Search skills– Search filters

• Appraiser? Digest producer?

Appraisal continuum

Searching

filtering

digests

appraising

teaching appraisal

Why should librarians get involved?• Extends and demonstrates

existing skills.• Other information sectors do it.• Area of research expertise• Value-added service• Improved profile/prestige

How are we getting involved today...

...Producing an evidence digest

Critically appraised resources• Systematic reviews

– telling the full story– e.g. Cochrane Library, NHS CRD, NHS HTA

• Guidelines– implementing the full story– SIGN, DEC, AHRQ, NIH

• Digests of evidence– giving a pointer in the right direction

Evidence-Based Digests

Study based

• NHS CRD DARE• NHS CRD NHS

EED• EB Journals• Best Evidence

Topic based

• ARIF• Clinical Evidence• Jnl of Clinical

Excellence• Evidence Matters

Aims

• To define a clinically relevant topic• To draw together a body of

relevant evidence• To identify key messages from the

best available evidence

Key messages

• Structured format• Indicative title• One line summaries• Levels of evidence and grades of

recommendation

This afternoon’s workshop• Producing a JCE style topic-based

digest

• Format and content• Techniques• Over to you!

Format

• Why important?– Relevance of topic, ‘burden of disease’

(to health service, society, individual), incidence and prevalence, key issues

• What is required?– Nature of the intervention

• Cost– Cost consequences of implementation

Format (cont.)

• Who is involved– Identification of interested parties

• Evidence– Key messages– Quality

• References– Of all sources consulted

Techniques

• Match evidence to message– Background = stats, official publications– Effectiveness = RCTs, systematic

reviews

• Authorise messages– Consider context– Keep wording from original source– Refer to source

Techniques (cont.)

• Keep it brief– Use ‘bullet points’– Break down complex ideas

• Make a start– Statements can be developed - or

replaced by better statements!

Over to you...

Support for Breastfeeding mothers

• Why important?• What is required?• Cost consequences• Interested parties• Evidence of effectiveness• References (Author, year, study type)

You have to help you...• Search results• Examples of JCE digests• Facilitators• Pens, paper, overheads• Time!

ResourcesforProducing Digests

Matching the evidence

• Background• Clinical effectiveness• Cost effectiveness

Background

• Official publications– Government and professional bodies

• Statistics– StatBase, WHO

• ‘Burden of disease’ to individual, health service and society– Cohort studies

Clinical Effectiveness

• Sources of systematic reviews, guidelines and digests

• TRIP database• SumSearch• PubMed Clinical queries• Medline filters

Cost effectiveness

• NHS CRD NHS EED and HTA• INAHTA Clearing House• Health Economics research units

– University of York CHE links page

• Medline filter