Quality Control Charts

Hi everybody;
I have a daily control material analyzed for certain chemical tests and the results values are being plotted as
"points" to show the performance of the machine and reagents.
I want these values to be represented as dots on the already prepared control chart as soon as I fill a daily table of the control values.
My attached file explains the problem.
Best Regards.

Originally Posted by mahju

Hi

First step is to get tge range for each value in your daily data e.g for 120 it is 111-121.
I use match function to do this (write the range in from to format (Even from can do)

secondly, In your chart Data range(On y-Axis) is not a number (70-79,80-89 etc) but excel required a numeric data so I use codes from 1 to 6. 70-79 is 1 and 80-89 is 2 and so on.
This is calculated by index function
Now you can draw chart taking day on X-axis and code on Y-Axis.
You can write actual range with the code but chart will be made on coding.
See the attached file also

It is a good step, but somehow sophisticated!
I wish it is handled in a more easier way.
thank you

Originally Posted by mahju

Hi

First step is to get tge range for each value in your daily data e.g for 120 it is 111-121.
I use match function to do this (write the range in from to format (Even from can do)

secondly, In your chart Data range(On y-Axis) is not a number (70-79,80-89 etc) but excel required a numeric data so I use codes from 1 to 6. 70-79 is 1 and 80-89 is 2 and so on.
This is calculated by index function
Now you can draw chart taking day on X-axis and code on Y-Axis.
You can write actual range with the code but chart will be made on coding.
See the attached file also

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

Originally Posted by Glenn Kennedy

Hi there. This will make a start on this. Two questions, to help me take this on a bit firther.

1. How are your upper & lower control limits set? What are they? Do they vary,according to the performance of your method, or are they fixed. If they vary, what rules are you usig to claculate them? I can then add them onto the chart.

2. Are you planning to have one of these for every month, or would it make more sense to have a continuous line of data, with the chart only displaying the last 30 days in a dynamic (constantly updating) manner?

Upper and lower limits are fixed for each type of test.
One chart is needed per test for each month

I wish it is clear
thank you!

Originally Posted by Glenn Kennedy

Hi there. This will make a start on this. Two questions, to help me take this on a bit firther.

1. How are your upper & lower control limits set? What are they? Do they vary,according to the performance of your method, or are they fixed. If they vary, what rules are you usig to claculate them? I can then add them onto the chart.

2. Are you planning to have one of these for every month, or would it make more sense to have a continuous line of data, with the chart only displaying the last 30 days in a dynamic (constantly updating) manner?

Upper and lower limits are fixed for each type of test.
One chart is needed per test for each month

I wish it is clear
thank you!

Originally Posted by Glenn Kennedy

OK, so to let me complete this chart, please tell me the value of the control levels and whatever name you want them labelled as on the graph. People from different lab backgrounds have their own names for these things...

I have completed the sheet with some imaginary numbers. The average column is dynamic - it is calculated off your data. The other control lines are fixed. Either change them yourself, to suit, or ask me.

If this meets your requirements, please mark the thread as solved. It would also be nice if you clicked the "add Reputation" button at the bottom of this post (and that of any others who also helped you reach a solution).

I'd like to thank you
First; I want to understand the steps how to do it
second; I want to show the UL and LL letters on the lines at y axis as well as the Mean.
finally, I want to connect the dots with line

Please give me steps

thank you in advance

Originally Posted by Glenn Kennedy

Firstly, I do not think that you should join the lines. That implies a relationship between the points. there isn't they're just QA data obtained on different days. (This is my line of work and I wouldn't join them. But it is YOUR decision. Let me know.


Secondly, I have given you two pairs of lines (amber & red). You still have to tell me the ACTUAL VALUES of the upper and lower control limits. You also need to tell me if you have one or two categories of lines (an "alert" line and an "Action" line, or just one. It sounds (from your last post) that there is just one.

I just put in some imaginary numbers - what are the real values?

We depend on "Levey Jenings chart" >>>>> An image is attached.
There should be 3 lines Up and 3 down and the midline is the target value
I know there are charts similar in Excel 2010 but I need more explanation
Although your values are imaginary but they are representative, Real value are obtained by depend on daily results which are updated monthly.

thank you

These results are varied according to the method. If we use the manufacturer values attached with control material then it is fixed, otherwise it is varied because we calculate our own mean and SD monthly.

Regards

Originally Posted by Glenn Kennedy

OK. It will be Monday before I finish this. But I know exactly what you want.

Hi,
It is now almost Wednesday..
I hope you're ready to proceed in my thread.


Lot of thanks

Originally Posted by Glenn Kennedy

Sorry about that. Too many airplanes in the last week...

How are these? One is based on fixed limits, which you must enter from the manufacturer's data. The other calculates SDs and enters them for you.

Are you sure that this is what you want? At the beginning of any month the charts are going to look a bit empty? Would it not be better if the chart showed the last 30 days data (or other interval specified by you)?

First let me say thank you for your commitment.
Second I want you to approve my amendments. I want to adopt those of fixed SD values.
third, If you please I want to learn how to make the graph after filling the columns with data, from where can I get them colored each with distinctive color.
Fourth, I want to connect the dots with lines
Fifth, How to hide columns of SDs upon finishing filling data.
Sixth, I want Control limits categories (+1SD, +2SD, -1SD, -2SD) to appear on the Y axis before its line.


I much appreciate your help.

Originally Posted by Glenn Kennedy

Here you are. Any further questions, please ask, otherwise, please mark the thread as closed & (preferably) say thanks to all who helped by clicking the "Add Reputation" button at the foot of their post(s).

I am grateful

thank you