American Journal of Clinical Nutrition, Vol 23, 178-188, Copyright © 1970 by The American Society for Clinical Nutrition, Inc.

Variation of Total Serum Cholesterol Concentration in Patients with Atherosclerosis

¹ From the Department of Medicine, The Long Island Jewish Hospital, New Hyde Park, New York 11040, and The Department of Mathematics, Queens College of the City University of New York, Flushing, New York 11367

Biologic variations of total serum cholesterol levels were studied in 12 patients with clinical evidence of arteriosclerosis for periods of 1-3 years. The data were subject to the following types of statistical analysis:

a) The means of 4, 6, 8, and 10 cholesterol values in respective chronological order were sequentially compared to the following identical number of cholesterol determinations, also in chronological order.

b) The means of 3, 4, 5, 6, and 7 cholesterol values in respective chronological order were compared with the means of the following 20 cholesterol values, also in chronological order.

c) The t's determined in parts a and b were subjected to a chi-square test for "goodness of fit" to the standard t distribution.

d) The cholesterol values in each patient were tested for randomness.

e) The data were analyzed for seasonal variations.

It was found, in parts a and b, that when the degree of significance was chosen at the 5% level, 12.5-26.9% of all comparisons between the two groups of cholesterol determinations showed statistically significant differences. When the level of significance was chosen at the 1% level, 2.9-16.1% of all comparisons were significantly different. Of the nine tests made for goodness of fit, six were rejected at the 5% level as having come from a standard t distribution. The hypothesis of randomness was rejected at the 5% level in 7 of the 12 patients. The nature of the variation of total serum cholesterol level was totally erratic. Analysis of the data failed to reveal any variation due to, or coinciding with, changes of seasons.