Evidence-based medicine databases 15-16.30 14 March 2006 Medical Library, Umeå UB Lars Iselid

How does a clinician choose the best intervention? The clinic’s less or more accepted, standard procedure of methods The opinions of an authority, for example a professor The method that is the most reliable based on scientific research - that’s EBM

The clinic’s less or more accepted, standard procedure of methods

The opinions of an authority, for example a professor

The method that is the most reliable based on scientific research - that’s EBM

Definition of Evidence-based medicine The process of systematically finding, appraising, and using contemporaneous research findings as the basis for clinical decisions. Evidence-based medicine asks questions, finds and appraises the relevant data, and harnesses that information for everyday clinical practice. The term "evidence based medicine" was coined at McMaster Medical School in Canada in the 1980's

The process of systematically finding, appraising, and using contemporaneous research findings as the basis for clinical decisions. Evidence-based medicine asks questions, finds and appraises the relevant data, and harnesses that information for everyday clinical practice.

The term "evidence based medicine" was coined at McMaster Medical School in Canada in the 1980's

The four steps in EBM formulate a clear clinical question from a patient's problem; search the literature for relevant clinical articles; evaluate (critically appraise) the evidence for its validity and usefulness; implement useful findings in clinical practice.

formulate a clear clinical question from a patient's problem;

search the literature for relevant clinical articles;

evaluate (critically appraise) the evidence for its validity and usefulness;

implement useful findings in clinical practice.

Scientifically verified - Evidence-Based Medicine (EBM) Help clinicians to make well-founded decisions on interventions Time-consuming finding all relevant clinical studies and compare them all by oneself Systematic reviews saves you time by doing the comparisions for you

Help clinicians to make well-founded decisions on interventions

Time-consuming finding all relevant clinical studies and compare them all by oneself

Systematic reviews saves you time by doing the comparisions for you

How to compile a systematic review? The authors identify an intervention for a specific disease or other problem in health care Locate, appraise and synthesize evidence from as many relevant scientific studies as possible Summarise conclusions about effectiveness Differs from other types of reviews Strict design Highly structured and systematic

The authors identify an intervention for a specific disease or other problem in health care

Locate, appraise and synthesize evidence from as many relevant scientific studies as possible

Summarise conclusions about effectiveness

Differs from other types of reviews

Strict design

Highly structured and systematic

EBM resources Cochrane Library database Clinical Evidence database EBM guidelines database

Cochrane Library database

Clinical Evidence database

EBM guidelines database

Archibald Cochrane (1909-1988) www.cochrane.org/docs/archieco.htm ” I had considerable freedom of clinical choice of therapy: my trouble was that I did not know which to use and when. I would gladly have sacrificed my freedom for a little knowledge. I had never heard then of 'randomised controlled trials', but I knew there was no real evidence that anything we had to offer had any effect on tuberculosis, and I was afraid that I shortened the lives of some of my friends by unnecessary intervention.” As a prisoner of war he discovered the lack of knowledge in the medical education Medical interventions should be based on scientific knowledge, not on presumption

” I had considerable freedom of clinical choice of therapy: my trouble was that I did not know which to use and when. I would gladly have sacrificed my freedom for a little knowledge. I had never heard then of 'randomised controlled trials', but I knew there was no real evidence that anything we had to offer had any effect on tuberculosis, and I was afraid that I shortened the lives of some of my friends by unnecessary intervention.”

As a prisoner of war he discovered the lack of knowledge in the medical education

Medical interventions should be based on scientific knowledge, not on presumption

Effectiveness and Efficiency. Random Reflections on Health Services, 1972 Clinical decisions should be based on knowledge, not on supposition or chances. In 1979 he wrote, " It is surely a great criticism of our profession that we have not organised a critical summary, by specialty or subspecialty, adapted periodically, of all relevant randomised controlled trials."

Clinical decisions should be based on knowledge, not on supposition or chances.

In 1979 he wrote, " It is surely a great criticism of our profession that we have not organised a critical summary, by specialty or subspecialty, adapted periodically, of all relevant randomised controlled trials."

Cochrane Collaboration international network, 1993, Oxford The aim : to help people make well informed decisions about health care by: preparing maintaining ensuring the accessibility of systematic reviews of the effects of health care interventions Principles Building on the enthusiasm of individuals Avoiding duplication Minimising bias Keeping up to date Selects RCT ’s - Randomized Controlled Trials and produces systematic reviews where all selected RCT’s(within the subject) are compared Updates the systematic reviews when new studies are available

The aim : to help people make well informed decisions about health care by:

preparing

maintaining

ensuring the accessibility of systematic reviews of the effects of health care interventions

Principles

Building on the enthusiasm of individuals

Avoiding duplication

Minimising bias

Keeping up to date

Selects RCT ’s - Randomized Controlled Trials and produces systematic reviews where all selected RCT’s(within the subject) are compared

Updates the systematic reviews when new studies are available

RCT-Randomized -controlled clinical trials - what’s that?? A trial where people randomly gets one or two(or more) clinical interventions Often treatment outcome, but also diagnostic methods, surgical procedures, screening programmes etc Randomizing patients randomly gets for example a new drug or the standard treatment (instead of the standard treatment sometimes placebo, for example sugar pills or no treatment at all)

A trial where people randomly gets one or two(or more) clinical interventions

Often treatment outcome, but also diagnostic methods, surgical procedures, screening programmes etc

Randomizing

patients randomly gets for example a new drug or the standard treatment (instead of the standard treatment sometimes placebo, for example sugar pills or no treatment at all)

RCT-Randomized -controlled clinical trials - what’s that?? Controlled means comparative. A control group is necessary, they get the the standard treatment (or placebo) Clinical trials the trial is made on humans (not animal trials)

Controlled

means comparative. A control group is necessary, they get the the standard treatment (or placebo)

Clinical trials

the trial is made on humans (not animal trials)

Structure 51 Collaborative review groups Airways grpup, Anaesthesia group, Back group, Breast Cancer group…) Reliable, up-to-date information relevant to prevention, treatment and rehabilitation of particular health problem Each group composed of people around the world who share an interest in developing and maintaining systematic reviews 10 Method groups 13 Cochrane Center Nordic Cochrane Center in Copenhagen

51 Collaborative review groups Airways grpup, Anaesthesia group, Back group, Breast Cancer group…)

Reliable, up-to-date information relevant to prevention, treatment and rehabilitation of particular health problem

Each group composed of people around the world who share an interest in developing and maintaining systematic reviews

10 Method groups

13 Cochrane Center

Nordic Cochrane Center in Copenhagen

Cochrane Library unique source of reliable and up-to-date information on the effects of interventions in health care Started 1995 Updating quarterly Contains 7 databases Published by Wiley Interscience Free for all internet users in Sweden www.sbu.se/filer/content0/dokument/presscochrane.html

unique source of reliable and up-to-date information on the effects of interventions in health care

Started 1995

Updating quarterly

Contains 7 databases

Published by Wiley Interscience

Free for all internet users in Sweden

www.sbu.se/filer/content0/dokument/presscochrane.html

The Cochrane Database of Systematic Reviews Cochrane Reviews Full-text systematic reviews which provide an overview of the effects of interventions in health care Each review covers a specific and well-defined area May include graphs with the data from each individual study Cochrane Protocols Provide information about reviews which are currently being written

Cochrane Reviews

Full-text systematic reviews which provide an overview of the effects of interventions in health care

Each review covers a specific and well-defined area

May include graphs with the data from each individual study

Cochrane Protocols

Provide information about reviews which are currently being written

Other databases in the Cochrane Library Database of Abstracts of Reviews of Effectivness (DARE) Structured abstracts of systematic reviews published in the scientific literature which are critically appraised and commented.

Database of Abstracts of Reviews of Effectivness (DARE)

Structured abstracts of systematic reviews published in the scientific literature which are critically appraised and commented.

Other databases in the Cochrane Library The Cochrane Controlled Trials Register (CENTRAL) Bibliography of publications which report on controlled trials. About 50% of all RCT from PubMed.

The Cochrane Controlled Trials Register (CENTRAL)

Bibliography of publications which report on controlled trials.

About 50% of all RCT from PubMed.

Other databases in the Cochrane Library Health Technology Assessment Database Bibliographic information to reports from International Network of Agencies for Health Technology Assessment (INAHTA), non-profit organizations like SBU ( The Swedish Council on Technology Assessment in Health Care) that evaluates healthcare technology. www.inahta.org

Health Technology Assessment Database

Bibliographic information to reports from International Network of Agencies for Health Technology Assessment (INAHTA), non-profit organizations like SBU ( The Swedish Council on Technology Assessment in Health Care) that evaluates healthcare technology.

www.inahta.org

Other databases in the Cochrane Library NHS economic evaluation of health care interventions … reliable information about the costs as well as the effects of drugs, treatments and procedures, to inform their decisions.

NHS economic evaluation of health care interventions

… reliable information about the costs as well as the effects of drugs, treatments and procedures, to inform their decisions.

Clinical Evidence The international source of the best available evidence of effective healthcare ( BMJ Publishing Group) Identify important clinical questions Search and summerise the best available evidence to answer them Systematic reviews (Cochrane Library, journals) Randomized controlled trials Concise format Show the gaps in the evidence The evidence must be individually interpreted Differences in individual patient’s risks and preferences Local availability of interventions

Identify important clinical questions

Search and summerise the best available evidence to answer them

Systematic reviews (Cochrane Library, journals)

Randomized controlled trials

Concise format

Show the gaps in the evidence

The evidence must be individually interpreted

Differences in individual patient’s risks and preferences

Local availability of interventions

EBM guidelines ”… a unique collection of concise and easy-to-use clinical guidelines for primary care combined with the best available evidence”. Produced in Finland.

”… a unique collection of concise and easy-to-use clinical guidelines for primary care combined with the best available evidence”.

Produced in Finland.