Deming's Insights on Control Charts for Workers

Improvement Insights Blog

Deming’s Insights on Control Charts for Workers

I was rereading Deming’s book “Out of the Crisis,” and discovered a way to use control charts that is new. Deming uses control charts to compare individual worker performance. Deming often asked leaders to drive out fear, but comparing individuals seems like a way to create fear unless you use the results to help train individuals to higher standards of performance. Here’s how:

“Hi, I’m Jay Arthur, author of “Lean Six Sigma Demystified” and QI Macros [software].

“I don’t know about you, but every once in a while I go back and re-read books about Quality. I’ve been getting back into Deming. This was published in 1986, so it’s about 35 years old, but it’s still relevant today. One of the things I found in here was he was using control charts; rather than on time series data, on more discrete data.

“So what we have here is he shows some welders and how many faults the welders have. If you take this data, [you can] highlight it with your mouse. If you know what you’re doing you could go choose a c chart, but the Control Chart Wizard [in QI Macros] would pick that one for you easily.

“So here you can see most of our welders are in control but one welder, number six, is out of control. Deming suggests that when people are in control, no amount of training will make them better. He even has examples from professional golfers, which I found interesting. But here you have one person who’s out of control and so training would be a useful thing to help them get back into some sort of performance control with everyone else. All right, so that’s a pretty simple application of a control chart.

“He also had some examples for inspectors and how many defects do the inspectors find. Again, we can take this data, Control Chart Wizard [in QI Macros] will ask if there can be more than one defect [per number] but in this case the answer is no, so we’re going to go with a p chart. Here you can see that… oh my gosh, like, everything’s out of control. So our inspection process is completely out of control, and so training everybody might really help out a bit here.

“Now the other thing is just comparing A, B, C, D inspectors. Now that’s kind of an interesting chart, isn’t it? The other interesting thing I find about this is that so many people rant and rave about, “Well, you need 20 points to do a control chart.” Well, Deming did one with four. Come on, all right?

“Here’s one from some data I have about physicians’ adverse events during deliveries of children. If we take that data right there, we can come up to the QI Macros and again, we can come in and choose a p chart. Here you can see most of them are in process control, but we have one MD, number one, who’s out of control, and so it would be useful to come back and give that doctor some training in how to avoid adverse events. We have some other people down here that are pretty low, and they might be the good people to train. So I find this was a pretty interesting way to use a control chart to compare performance of different people on different types of data.

“So that’s my Improvement Insight for this week. Use QI Macros, compare people, figure out who needs the training, figure out who doesn’t need more training. Once you’re… once you’re in statistical process control, the only thing Deming says that will change this is to change the system and who controls the system? Leadership. All right?

“That’s my Improvement Insight for this week. Let’s go out and improve something this week.”