Additional material

Section A: Information about systematic review methods

Databases searched and search terms

Databases searched / Most recent issue or date searched and comments
Cochrane Library / 1999 Issue 4 for trials and systematic reviews
CRD Database of Abstracts of Reviews of Effectiveness (DARE) via the web / On 27/10/99 for systematic reviews
CRD Health Technology Assessment (HTA) database / On 6/10/99
GEARS (Getting Easier Access to Reviews) / 1999 version (June) for general reviews
Best Evidence 3 / 1999
Medline / 1966-10/1999 for trials, cost papers and systematic reviews (brief search for economic evaluations updated to include 1997-12/2000)
‘Pre-Medline’ via InterNet Grateful Med / On 6/10/99 restricted to 1997-1999
Embase / 1980-08/1999 for trials and cost papers (brief search for economic evaluations updated to include 7/99-2/2001)
BIOSIS / On 11/10/99 – for meeting abstracts only
Science Citation Index / On 11/10/99 – for meeting abstracts only
NHS EED / On 5/2/2001 for economic evaluations
EconLit / 1969-01/2001 for economic evaluations
National Research Register (NRR) / 1999 Issue 2
The meta Register of Controlled Trials ( / On 22/12/99
Using Mesh terms:
  • heparin,-low-molecular-weight or low-molecular-weight-heparin
  • enoxaparin
  • unstable angina or Angina,-Unstable
  • myocardial-infarction or heart-infarction
  • randomized-controlled-trial(s)
  • randomization or random-allocation
  • double-blind-procedure or double-blind-method
  • single-blind-method
  • product-surveillance-postmarketing
  • adverse-drug-reaction-reporting-systems
  • drug-toxicity
  • costs-and-cost-analysis
  • cost
  • economic-evaluation
Additional information from:
  • Bibliographies of papers assessed for further relevant studies
  • Product manufacturers of low molecular weight heparins (to check for further trials and general information)
  • Web sites
  • Cardiology experts
/ Using text words:
  • low molecular weight heparin* or (low and molecular and weight and heparin)
  • enoxaparin
  • unfractionated or non-fractionated or nonfractionated or standard
  • heparin*
  • unstable angina or (unstable and angina) or unstable-angina-pectoris
  • heart attack or (heart and attack)
  • coronary and occlusion
  • infarct*
  • cardiac
  • cardial
  • heart
  • myocardial
  • myocardium
  • transmural
  • subendocardial
  • (non q wave) or (non-q-wave) or (non and Q and wave) or (non-Q and wave)
  • random*
  • double or single and blind*
  • mask*
  • (adverse or side) and effect*
  • bleeding or thrombocytopenia

Databases searched and search terms (continued)

Studies valuing the health states (myocardial infarction and unstable angina)
Databases searched:
Medline 1966 to October 1999
Embase 1980 to August 1999
EconLit 1969 to September 1999 / Search strategy:
  • rosser-r* in author; rosser in title or abstract; QALY*; euroqol; EQ5D; EQ-5D
  • AND (cardi* or heart or coron* or myocardial* or angina).

Inclusion criteria for effectiveness data for modelling

  • Papers in English.
  • Systematic reviews of comparative RCTs, or comparative RCTs (ie excluding placebo controlled trials).
  • Patients: People with unstable angina or non-Q-wave myocardial infarction.
  • Intervention: Infusion of intra-venous unfractionated heparin compared with low molecular weight heparins, although cost-utility analysis was restricted to enoxaparin.
  • Outcomes: Patient based outcomes (ie not physiological outcomes alone), eg outcomes used in the clinical trials (death, myocardial infarction, recurrent angina), requirements for revascularisation (coronary artery bypass grafting and percutaneous transluminal coronary angioplasty) and adverse effects such as bleeding and thrombocytopenia.

Critical appraisal/data extraction methods for effectiveness data

The author applied the inclusion criteria, extracted data and undertook critical appraisal of identified studies using the CRD checklist[1]. In addition, the papers were scored for quality using the Jadad instrument [2]. Where there was uncertainty a second reviewer was consulted.

Section A: References

  1. Undertaking systematic reviews of research on effectiveness. CRD guidelines for those carrying out or commissioning reviews. 4. 1996. York, NHS Centre for Reviews and Dissemination.
  2. Jadad AR, Moore RA, Carroll D, Jenkinson C, Reynolds DJ, Gavaghan DJ et al.: Assessing the quality of reports of randomized clinical trials: is blinding necessary?Control Clin Trials 1996, 17: 1-12.

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