Blood Chemistry

In pharmacologic research a variety of clinical chemistry

measurements are routinely monitored closely for evidence

of side effects of the medication under study. Suppose

typical blood-glucose levels are normally distributed, with

mean = 90 mg/dL and standard deviation = 38 mg/dL.

5.31 If the normal range is 65−120 mg/dL, then what percentage

of values will fall in the normal range?

5.32 In some studies only values at least 1.5 times as high

as the upper limit of normal are identified as abnormal. What

percentage of values would fall in this range?

5.33 Answer Problem 5.32 for values 2.0 times the upper

limit of normal.

5.34 Frequently, tests that yield abnormal results are repeated

for confirmation. What is the probability that for a

normal person a test will be at least 1.5 times as high as the

upper limit of normal on two separate occasions?

5.35 Suppose that in a pharmacologic study involving 6000

patients, 75 patients have blood-glucose levels at least 1.5

times the upper limit of normal on one occasion. What is the

probability that this result could be due to chance?