Abstract
Individuals with a high cholesterol level (greater than 6.5 mmol/L) are at a relatively high risk of developing coronary heart disease in the future and an important part of any programme to prevent coronary heart disease is the identification and treatment of these individuals. Mass screening can identify those who are at an increased risk but the likely benefits and costs of such a programme have not been assessed adequately. Before such a method is promoted, we need to know: how well it detects high-risk individuals (yield); what reductions in the risk of coronary heart disease can be expected in those who are screened as "positive"; what adverse effects screening may have on those who are screened as "negative"; and what the logistics and costs (both to those who are screened and to the community as a whole) are. Until we know this information the urge to promote mass screening for cholesterol levels should be restrained, and only those who are at high risk of coronary heart disease should be selected for the determination of their cholesterol levels.