TY - JOUR
T1 - Estimating an Individual’s True Cholesterol Level and Response to Intervention
AU - Irwig, Les
AU - Glasziou, Paul
AU - Wilson, Andrew
AU - Macaskill, Petra
PY - 1991/9/25
Y1 - 1991/9/25
N2 - An individual’s blood cholesterol measurement may differ from the true level because of short-term biological and technical measurement variability. Using data on the within-individual and population variance of serum cholesterol, we addressed the following clinical concerns: Given a cholesterol measurement, what is the individual’s likely true level? The confidence interval for the true level is wide and asymmetrical around extreme measurements because of regression to the mean. Of particular concern is the misclassification of people with a screening measurement below 5.2 mmol/L who may be advised that their cholesterol level is "desirable" when their true level warrants further action. To what extent does blood cholesterol change in response to an intervention? In general, confidence intervals are too wide to allow decision making and patient feedback about an individual’s cholesterol response to a dietary intervention, even with multiple measurements. If no change is observed in an individual’s cholesterol value based on three measurements before and three after dietary intervention, the 80% confidence interval ranges from a true increase of 4% to a true decrease of 9%.
AB - An individual’s blood cholesterol measurement may differ from the true level because of short-term biological and technical measurement variability. Using data on the within-individual and population variance of serum cholesterol, we addressed the following clinical concerns: Given a cholesterol measurement, what is the individual’s likely true level? The confidence interval for the true level is wide and asymmetrical around extreme measurements because of regression to the mean. Of particular concern is the misclassification of people with a screening measurement below 5.2 mmol/L who may be advised that their cholesterol level is "desirable" when their true level warrants further action. To what extent does blood cholesterol change in response to an intervention? In general, confidence intervals are too wide to allow decision making and patient feedback about an individual’s cholesterol response to a dietary intervention, even with multiple measurements. If no change is observed in an individual’s cholesterol value based on three measurements before and three after dietary intervention, the 80% confidence interval ranges from a true increase of 4% to a true decrease of 9%.
UR - http://www.scopus.com/inward/record.url?scp=0025770273&partnerID=8YFLogxK
U2 - 10.1001/jama.1991.03470120080037
DO - 10.1001/jama.1991.03470120080037
M3 - Article
C2 - 1886192
AN - SCOPUS:0025770273
SN - 0098-7484
VL - 266
SP - 1678
EP - 1685
JO - JAMA: The Journal of the American Medical Association
JF - JAMA: The Journal of the American Medical Association
IS - 12
ER -