+-1,2,3,4,5,6,7,9,10,12 SD Levey Jennings graph Quality control Rejection and voilation of rules

1. By:
Zahid Ismail Bughlani

2.  This test is used to check either the quality control
value that we run on daily basis in our laboratories is
running well or not.
 Either the LJ graph is normal or abnormal. To rule out
this, westgard rule is very important.

3.  Every control that we run is plotted on LJ graph. LJ graph
has x and y axis. On X axis there will be no of days/time
while on y axis there will be value of mean and standard
deviation (difference between mean and actual value.

4.  So we daily run our control on LJ graph and our values
are plotted on this graph and graph is drawn. Now in
automatic, Westgard rule can be activated directly.
There following 8 major rules and 3 other multi rules
for LJ graph in Westgard Rules.
 Nowadays the automations find the SD automatically.
It may be performed by drawing the graph and the SD
will be known to us by kit.

5.  13S refers to a control rule that is commonly used with a
LJ chart when the control when the control limits are
set as the Mean plus 3s and the Minus 3s. A run is
rejected when a single control measurement exceeds
the mean plus 3s or mean minus 3s control limit.

7.  12s refer to controla control rule that is commonly used
with a LJ chart when the control limits are set as the
Mean plus 3s and the Minus 3s. In the original
multirole QC, it is used as a warning rule TO TRIGGER
the careful inspection of the control data by following
rejection rule.

9.  It reject when 2 consecutive control measurements
exceed the same mean plus/minus control limit.

10.  It rejects when 4 consecutive control measurements
exceed the same mean plus 2s or same mean minus 2s
control limit.

11.  It rejects when 4 consecutive control measurements
exceed the same mean plus 2s or same mean minus 2s
control limit.

12.  It rejects the run when 10 consecutive control
measurements fall on one side of the mean. This is
usually due to systemic error.

13.  It rejects when 8 consecutive control measurements
fall on the one side of the mean.

14.  12x reject when 12 consecutive control
measurements fall on one side of the mean. The
preceding control rules are usually used with N's of 2or
4, which means they are appropriate when two
different control materials are measured 1 or 2 times
per material.

15.  These violations show inappropriate or any error due
to reagent. It may also be due to the change in lot and
not calibrating the instrument properly.

16.  It rejects when 2 consecutive control measurements
exceed the same mean plus 2s or mean minus 2s
control limit.

17.  It rejects when 3 consecutive control measurements
exceed the same mean plus 1s or mean minus 1s
control limit.
 While in 13S Rule, single control measurement exceeds
the mean plus 3s or mean minus 3s control limit.

18.  It rejects when 6 consecutive control measurements
fall on the one side of the mean.

19.  It rejects when 7 consecutive control measurements
fall on the one side of the mean.
 This happens in TREND.

20.  It rejects when 9 consecutive control measurements
fall on the one side of the mean.

21. Trend Shift
Continuous movement of values in one
direction over six or more analytical
runs
Sudden change of values from one level
of control chart to another level
May be caused by deterioration of
reagent, tubing or fused bulb of
instrument
Common cause of shift is failure to
recalibrate, when changing lot no of
reagents.

22.  Trend Shift