Estimation of reference ranges: how many subjects are needed?
We measured Na, K, Cl, glucose, hemoglobin, erythrocytes, and hematocrit in the serum or blood from approximately 800 male and 200 female second-year medical students in an effort to define the size of an acceptable reference population. Using the data from the men and Monte Carlo simulations of 10-400 samples, each carried out 5000 times, we found that for most of the above tests, approximately 200 people are required for stable lower (2.5%) and upper (97.5%) reference limits to be obtained. This agrees with the 198 subjects required by strictly statistical criteria to define the same limits with a 99% confidence level.
Lott
J A
JA
Department of Pathology, Ohio State University, Columbus 43210.
Mitchell
L C
LC
Moeschberger
M L
ML
Sutherland
D E
DE
D000328:Adult; D001786:Blood Glucose / Q000032:analysis*; D003625:Data Collection / Q000379:methods*; D004573:Electrolytes / Q000097:blood*; D004906:Erythrocyte Count; D005260:Female; D006400:Hematocrit; D006454:Hemoglobins / Q000032:analysis*; D006801:Humans; D008297:Male; D011786:Quality Control; D012016:Reference Values
D001786:Blood Glucose; D004573:Electrolytes; D006454:Hemoglobins