For this problem, you may need to work off-line. After you have evaluated the data on the following page, return to the course and answer the accompanying questions.

Problem
You are the only full-time employee at a small clinic's laboratory. You use an assayed control for your glucose determinations. The manufacturer's printed values for the present lot number are:

• Level 1 Control
  • Mean: 72 mg/dL
  • Standard deviation: +/- 2 mg/dL
• Level 2 Control
  • Mean: 281 mg/dL
  • Standard deviation: +/- 12 mg/dL

The table on the next page shows that control results for the first twelve days of testing for the month. Plot your QC results on a Levey-Jennings chart and evaluate your data.