When Analyzing a Blood Gas Control Sample, You Notice That

Multiple Choice

When analyzing a blood gas control sample, you notice that the result falls outside the 2 SD range. How could you verify that this was a random error (error of imprecision) ?
1) Repeat the analysis on a different analyzer.
2) Compare the control to an actual patient sample.
3) Rerun the control sample a second time.

A) 1 and 2 only
B) 1 and 3 only
C) 2 and 3 only
D) 1, 2, and 3