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To examine the accuracy of a new version of the Sheffield table designed to aid decisions on lipids screening and detect thresholds for risk of coronary heart disease needed to implement current guidelines for primary prevention of cardiovascular disease.Comparison of decisions made on the basis of the table with absolute risk of coronary heart disease or cardiovascular disease calculated by the Framingham risk function. The decisions related to statin treatment when coronary risk is/=30% over 10 years; aspirin treatment when the risk is/=15% over 10 years; and the treatment of mild hypertension when the cardiovascular risk is/=20% over 10 years.The table is designed for use in general practice.Random sample of 1000 people aged 35-64 years from the 1995 Scottish health survey.Sensitivity, specificity, and positive and negative predictive values of the table.13% of people had a coronary risk of/=15%, and 2. 2% a risk of/=30%, over 10 years. 22% had mild hypertension (systolic blood pressure 140-159 mm Hg). The table indicated lipids screening for everyone with a coronary risk of/=15% over 10 years, for 95% of people with a ratio of total cholesterol to high density lipoprotein cholesterol of/=8.0, but for50% with a coronary risk of5% over 10 years. Sensitivity and specificity were 97% and 95% respectively for a coronary risk of/=15% over 10 years; 82% and 99% for a coronary risk of/=30% over 10 years; and 88% and 90% for a cardiovascular risk of/=20% over 10 years in mild hypertension.The table identifies all high risk people for lipids screening, reduces screening of low risk people by more than half, and ensures that treatments are prescribed appropriately to those at high risk, while avoiding inappropriate treatment of people at low risk.

OBJECTIVE--To evaluate the long term efficacy of diets in lowering serum cholesterol concentration. DESIGN--Descriptive overview of 16 published controlled trials of six months9 duration or longer. SETTING--Trials had been conducted in hospital clinics (6), industry (3), mental hospitals or institutions (3), and in general populations (4). PATIENTS--Trials had been conducted in high risk subjects (5), in unselected healthy subjects (6), or for secondary prevention in patients with coronary heart disease (5). Women were included in only four trials. INTERVENTIONS--Diets equivalent to the step 1 diet were employed in eight trials, with individual intervention by dietitians (3) or occupational physicians (2) or with population advice (3). Intensive diets which were more rigorous than the step 2 diet were employed in eight trials. MAIN OUTCOME MEASURES--Net change in serum total cholesterol concentration in subjects receiving treatment with diet compared with values in control subjects after six months to 10 years. RESULTS--In five trials with the step 1 diet as individual intervention the net reduction in serum cholesterol concentration ranged from 0% to 4.0% over six months to six years. In trials with population education reductions in cholesterol concentrations were 0.6-2.0% over five to 10 years. When population and individual dietary advice were combined changes in cholesterol concentration ranged from a fall of 2.1% to a rise of 1.0% over four to 10 years. Diets more intensive than the step 2 diet reduced serum cholesterol concentration by 13% over five years in selected high risk men in the population; by 6.5-15.1% over two to five years in hospital outpatients; and by 12.8-15.5% over one to four and a half years in patients in institutions. CONCLUSIONS--The response to a step 1 diet is too small to have any value in the clinical management of adults with serum cholesterol concentrations above 6.5 mmol/l. Current guidelines recommend screening of serum cholesterol concentration in healthy subjects, followed by treatment with a step 1 diet. The guidelines should be reviewed to provide a more realistic estimate of the effect of a step 1 diet and of the likely need for lipid lowering drugs.

EDITOR—Two letters last December on the use of statins, by Betteridge et al (p 1619) and Reynolds et al (p 1620), criticised the Sheffield table.1 The rate of coronary heart disease events targeted (3% per year) is not “arbitrarily high,” as Reynolds et al say, but was proposed after consideration of the number needed to treat, cost effectiveness, proportion of adults needing treatment, and total cost of treatment at different thresholds of risk of coronary heart disease.2 The European task force's guidelines3 which suggested the 2% per year threshold for coronary heart disease preferred by the letters' authors predated the statin trials. We do not accept that high risk people over age 65 should be denied treatment,1 and treating those below age 65 with a relative risk of coronary heart disease of 41 seems unwise. A 35 year old woman with a total cholesterol concentration of 7.0 mmol/l, systolic blood pressure of 160 mm Hg, and no other risk factors has a relative risk …

EDITOR,--The OXCHECK study showed significant reductions in total cholesterol concentration (3.1%) and blood pressure (2.5/1.5 mm Hg) with health checks over three years.1 The reductions in cholesterol concentration are in line with responses shown in previous controlled trials.2 The authors seem in some doubt about whether these effects are large enough to justify the cost of the health checks. This may be clearer when the projected …