2. You are also tasked with establishing a Levy-Jennings chart for the new lot number of normal
K+ controls. You run 20 consecutive days of QC and receive the following results:
3.8, 4.2, 4.5, 3.8, 4.3, 4.7, 4.8, 4.8, 4.6, 5.2, 5.0, 5.4, 5.0, 5.2, 5.2, 4.8, 4.9, 3.8, 4.2, 4.6
Standard Deviation: .50
a. What is your mean value?
b. What is your reference range at the 95% confidence level?
c. Chart your results on the Levy-Jennings chart below. Circle any out of control data
points, as well as identifying any shifts or trends.
d. What could be a possible cause of any of the aberrant QC results that you found?
3. What is the purpose of a reagent blank?