User's Manual

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Other information
Ŷ Quaility control policy
Westgard multi-rule technique
Ŷ Levey-Jenning Approach
1:2S Warning rule: 1 control outside 2SD and 1 control within 2SD.
1:3S Rejection rule (random error): 1 of the controls is outside 3SD.
2:2S Rejection rule (systematic error): 2 consecutive controls are outside 2Sd. The problem
should be corrected before running the control again.
R:4S Rejection rule (random error): 1 control is outside 2SD in one direction 1 control is
outside 2SD in the other direction (separating them by 4SD).
4:1S Rejection rule (systematic error): 4 consecutive controls exceed the same mean plus or
minus 1SD.
10:mean Rejection rule (systematic error): 10 consecutive controls fall on one side of the
mean (shift).