Michele L' Hales

1
Systematic Reviews,
The Cochrane Collaboration

• Michele L. Hales
• University of Alberta
• Edmonton, AB CANADA

Dubai, U.A.E.
October 2nd 3rd, 2003
2
The Cochrane Collaboration

• "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".
• -- Archie Cochrane, 1979

3
The Collaboration is being built on a set of
eight values

• Collaboration
• Building on the enthusiasm of individuals
• Avoiding duplication
• Minimizing bias
• Keeping up to date
• Ensuring relevance
• Ensuring access
• Continually improving the quality of work

M. Haugh and D. Fouque. Evidence-based
nephrology. Nephrol Dial Transplant (1999) 14
Suppl 3 38-41
4

• The Cochrane Collaboration is an international
  network of health care professionals, researchers
  and consumers who are interested in developing
  and maintaining comprehensive, regularly updated
  critical reviews of evidence from randomised
  clinical trials relevant to their specialty and
  interests.

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Brief History

• The first systematic reviews were in the field of
  Pregnancy and Childbirth.
• Increased interest from professional groups,
  health managers, and government organisations in
  extending the scope of systematic reviews.
• The Cochrane Database of Systematic Reviews is
  now published quarterly in the electronic journal
  The Cochrane Library.

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Cochrane Centres

• Cochrane Centres have been established in a
  number of countries world-wide, funded by both
  government and charitable sources.
• Responsible for maintaining registers of known
  randomised controlled trials, complete systematic
  reviews as well as current and potential
  contributors to the Collaboration.
• Provide advice and training to those who
  contribute to the Collaboration .

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The Cochrane Renal Group (CRG)

• The Cochrane Renal Group (CRG) began March 1,
  1997.
• The Cochrane Renal Group (CRG) is one of 50
  Cochrane Collaboration review groups around the
  world and consists of individuals who share a
  common interest in renal disease. Members of the
  group include reviewers, handsearchers, referees,
  consumers, government as well as the editorial
  team.

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What is a systematic review?

• A reviewer must
• identify an intervention for a specific disease,
  and ask whether or not this intervention works.
• Its accomplished by
• locating, reviewing and assessing evidence from
  as many relevant scientific studies as possible.
  
• summarising the conclusion with respect to its
  effectiveness
• providing the summary as a unique collation of
  the known evidence on a given topic.

At this point, the primary studies for any
intervention are made available for others to
review.
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Validity Guide of the SR

• Is this a systematic review of randomised trials?
• Does this systematic review have a methods
  section that describes
• Finding and including all relevant trials
• How the validity of the individual studies was
  assessed?
• Were the results consistent from study to study?

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Importance of SR Validity Results

• What is the magitude of the treatment effect?
• How precise is the treatment effect?

Are the valid results of this SR applicable to
our Patient?

• Is our patient so different from those in the
  study that its results?
• How precise is the treatment effect?
• What are our patients potential benefits and
  harms from the therapy?
• What are our patients values and preferences for
  both the outcome we are trying to prevent and the
  side-effects we may cause?

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Renal Reviews

• Responsibilities include
• Identify all trials concerning renal diseases
• Assess the trials for relevance and quality
• Assemble and analyse the trial data
• Prepare structured reports for inclusion in the
  Cochrane Database of Systematic Reviews

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CRGs Focus

• The Cochrane Renal Group's focus includes the
  following major areas of renal disease
• Acute renal failure
• Chronic renal failure
• Dialysis both peritoneal and haemodialysis
• Renal transplantation
• Renovascular hypertension
• Glomerular diseases
• Urinary tract infections
• Nephrolithiasis

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Areas of High Priority

• Renal Transplantation
• Tacrolimus for renal transplant recipients
• Antilymphocyte preparations for renal transplant
  recipients
• IL-21 receptor blockers for renal transplant
  recipients
• Sirolimus for renal transplant recipients
• Dialysis
• Interventions to prevent peritonitis exit site
  infections in peritoneal dialysis
• Treatment for dialysis-related hypotension
• General Nephrology
• Corticosteroids for minimal change nephropathy in
  adults
• Interventions to prevent contrast-induced
  nephropathy
• Interventions to reduce infection risk in
  nephrotic syndrome
• Interventions to reduce thrombosis risk in
  nephrotic syndrome

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Trials in Nephrology

• Published Trials (4100)
• Ongoing Trials (57)

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Current Trials

• Acute Renal Failure (1)
• Diabetic Nephropathy (4)
• Dialysis (17)
• General Nephrology (14)
• Transplantation (17)
• Urinary Tract Infection (3)

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Current Trials

• Acute Renal Failure (1)
• Effects of different doses in continuous
  veno-venous haemofiltration on outcomes of acute
  renal failure a prospective randomised trial.
• Diabetic Nephropathy (4)
• Dual blockade of the renin-angiotensin system in
  type 1 patients with diabetic nephropathy
• Effect of dietary protein restriction on
  prognosis in patients with diabetic nephropathy
• The role of angiotensin II receptor blockers in
  preventing the progression of renal disease in
  patients with type 2 diabetes.
• Dual blockade of the renin-angiotensin system
  versus maximal recommended dose of ACE inhibition
  in diabetic nephropathy.

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Current Trials Contd

• Dialysis (17)
• Transferrin saturation versus reticulocyte
  hemoglobin content for iron deficiency in
  Japanese hemodialysis patients.
• Creatine monohydrate treatment alleviates muscle
  cramps associated with haemodialysis.
• Effect of dialysis dose and membrane flux in
  maintenance hemodialysis.
• A controlled, prospective study of the effects of
  atorvastatin on proteinuria and progression of
  kidney disease.
• Effects of long and short hemodialysis on
  endothelial function A short-term study.
• Effects of raloxifene on bone metabolism and
  serum lipids in postmenopausal women on chronic
  hemodialysis.

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Current Trials Contd

• General Nephrology (14)
• Reduction of proteinuria combined effects of
  receptor blockade and low dose angiotensin-convert
  ing enzyme inhibition. see comments.
• Renoprotective effect of small doses of losartan
  and enalapril in patients with primary
  glomerulonephritis. Short-term observation.
• Effects of combined ACE inhibitor and angiotensin
  II antagonist treatment in human chronic
  nephropathies.
• Carvedilol increases two-year survival in
  dialysis patients with dilated cardiomyopathy a
  prospective, placebo-controlled trial.
• Antihypertensive treatment with and without
  benazepril in patients with chronic renal
  insufficiency a US economic evaluation.

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The Cochrane Library

• It is a one of a kind source of reliable, up to
  date information on the effects of interventions
  in health care. Todays healthcare needs to
  include the best information on the effectiveness
  of each intervention being accessible to
  practitioners, patients, and policy makers. This
  is evidence-based medicine.
• The library is designed to provide information
  and evidence to support decisions taken in health
  care and to inform those receiving care.

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Cochrane Library

• The Library includes
• Full text, including graphs, of the original
  systematic review
• Quality assessed information
• Critical appraisals of high-quality reviews
  published elsewhere
• A number of very useful accompanying databases

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Searches Library Database

• Search by specific topic
• Combine words or phrases to modify the meaning of
  a search
• Searches can be refined by selecting date ranges,
  document status, or by titles or authors only
• The history screen grabs each search for future
  retrieval or to combine with new search terms

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MeSH Thesaurus

• The library provides a MeSH search facility as an
  added search aid
• The MeSH thesaurus is published by the NLM
• Has a vocabulary of 15,000 terms for precise
  description of the medical documents content
• Terms are arranged as a tree structure which
  links related terms.
• Terms can be further defined by the addition of
  qualifiers

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The Renal Health Library

• It contains
• relevant systematic reviews on kidney disease
  from the Cochrane Database of Systematic Reviews
• references to over 4000 randomised controlled
  trials in kidney disease from the Cochrane Renal
  Group's Renal Trials Register, including 650
  abstracts from conference proceedings
• over 50 reports of ongoing randomised controlled
  trials
• information about the Cochrane Collaboration, the
  Cochrane Renal Group and the systematic review
  process

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Renal Health Library CD

• May 2003 (1st Issue)
• Contains over 4000 randomised controlled trials,
  including ongoing trials, with links to abstracts
  on PubMed and 36 full-text reviews in nephrology.

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Contact Information

• Cochrane Renal Group
• Centre for Kidney Research
• The Childrens Hospital at Westmead
• NSW 2045 Australia
• tel [phone]
• fax [phone]
• e-mail crg_at_chw.edu.au
• website www.cochrane-renal.org