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Testing Lean Changes, Small or Large


By Mark Graban, Vice President of Improvement and Innovation Services
Published: July 31, 2016


Lean is about teams and organizations working together in the continuous pursuit of perfection (even if we never quite get there). Improvement means change, which therefore means risk, as we might try something that doesn’t work (or has side effects). Too many organizations create overly-cautious leaders who make employees afraid to try anything new because they might stumble or fail. Lean gives us mindsets and tools to minimize the risks involved with change while moving progress forward.

For the past 11 years, I've been teaching and coaching healthcare organizations on the adoption of Lean principles and practices, working to improve safety and quality, create better workplaces, and reduce costs (among other goals). Before that, I worked for ten years in manufacturing, starting as an industrial engineer at General Motors. Lean leadership principles, at a high-level, are incredibly consistent and applicable across various industries. We’re a Lean-thinking organization if we, among other things, focus on customers, engage employees, and use scientific methods to improve and redesign the way we do our work.

Check out Mark's book Lean Hospitals for more on this subject.

Staff-driven continuous improvement is, of course, one of the main pillars of the Lean management approach. We call this "Kaizen,” meaning “good change” or “continuous improvement.” Formal, weeklong team-based projects called "Kaizen Events" (or sometimes called “Rapid Improvement Events" in healthcare) can be great for solving relatively big, more complicated problems or they can be used to redesign systems or parts of a value stream. But, the real essence of Kaizen, as practiced at Toyota and leading health systems, is getting everybody involved in improvement, every day. Or, at least that's the ideal.

Everybody has the potential to speak up to point out problems and opportunities for improvement related to their work. Leaders need to create an environment where people actually feel safe to do so. Leaders must ask employees for their ideas and then allow them to test ideas to see if the change really is an improvement. Kaizen follows the proven "Deming Cycle" of Plan, Do, Study, Adjust. We don’t just try something and assume it will work (or worse yet, rationalize or justify it regardless of the real results).

Change is scary…

It’s part of our human nature and the way our brains are wired (see the excellent book The Spirit of Kaizen by Robert Maurer, PhD for more on this).  Instead of lecturing people to somehow not to be afraid of change, there are a few more effective strategies that we can use. For one, we can involve people instead of forcing changes on them. Secondly, we can make sure we properly understand a problem and its causes, so we’re doing a better job of anticipating which countermeasures or changes might work best. Thirdly, we can do a “small test of change,” trying a proposed change in one area or one site… to first Plan and Do on a small scale so we can Study that small change and Adjust if needed.

There are many small Kaizen changes where we can easily and painlessly “click undo” on the change. We can Plan a bit but have a bias to quickly Do and then Study. You want to move that printer over a few feet? OK, try it, because we can always move it back. There’s no risk in trying.

For larger changes, we can test our change in some sort of simulated environment. If we’re proposing to change the layout of a production cell or a hospital lab, we can use paper “tabletop simulations” to mentally walk through different aspects of the proposed change before we take action on the physical space. In recent years, many organizations have used “Lean Design” methods (sometimes called “3P” or the Production Preparation Process). I’ve helped organizations build life sized cardboard mockups of their spaces so they can simulate new ways of working. It’s less expensive and less troubling to discover that it’s hard to push a patient bed around a particular corner when the actual wall hasn’t been built yet. The idea is to make mistakes and adjust early in the process via a simulation instead of in the real world. We can learn through failure, but we need to make the failures as small as possible.

Evaluating Changes

There are some changes that we can’t evaluate properly through physical simulations. Sometimes the safest way to test a change is through a computer simulation. When I worked as an engineer at GM, I was proposing some changes to the way we buffered inventory around machines on our engine block machining line. The old way was to store inventory between every and any operation, which caused ergonomic problems and quality risks. I used discrete event simulation software to prove out that having buffers at just a few locations could have the same effect as the “everywhere and anywhere” strategy.

In healthcare, simulation can be useful in testing our hypothesis about the right number of exam rooms, registration desks, beds, or whatever. Given that we have valid input data (which is often a challenge in healthcare), a simulation is a lower-risk way of testing a new strategy. Let’s say we think we can build an emergency department with just 18 rooms instead of 24 because of improved flow and better processes. Even though 18 rooms is cheaper, the hospital might be scared to go that route since waiting times could suffer if the prediction is wrong that 18 beds would work fine. Simulation allows us to test that change to see if it’s really going to be an improvement – or at least being more certain about it – instead of the risky approach of “build it and see.”

Either way, Lean practitioners should remind themselves to test potential changes whenever possible. Some changes are small enough (and un-doable enough) where we can just try. But many changes lend themselves to small tests of change in some sort of simulation space… to me, that’s Lean thinking.


The Author

Mark Graban

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