Study designs of evaluations included in the review
Randomised controlled trials (RCTs) were eligible for inclusion. These had to employ concealment allocation, except for dietary interventions. The follow-up periods in the included studies ranged from 3 to 6.1 years.
Specific interventions included in the review
Studies that compared a single predominantly LDL-C-lowering treatment given for over 2 years with placebo were eligible for inclusion. The included studies investigated the effects of specific diets, bile acid sequestrants, surgery and statins. The statins used were simvastatin, pravastatin, lovastatin, fluvastatin and atorvastatin.
Participants included in the review
The review did not state any inclusion criteria for the participants. The patients in the included studies were CHD patients, high- or moderate-risk patients, and patients with other cardiovascular diseases (stroke, transient ischaemic attack, peripheral arterial disease), renal transplants or diabetes. Many samples were male only.
Outcomes assessed in the review
Studies that reported clinical effects and used nonfatal myocardial infarction (MI), CHD death, and fatal and nonfatal ischaemic stroke as primary or secondary outcomes were eligible for inclusion. The review focused on relative risk reductions and the percentage change in LDL-C. Percentage reductions in LDL-C, nonfatal MI or CHD and/or death, and stroke (fatal or nonfatal) were reported.
How were decisions on the relevance of primary studies made?
The authors did not state how the papers were selected for the review, or how many reviewers performed the selection.