<Bob> Good afternoon Lesley, can I suggest a topic today?
<Lesley> Hi Bob. That would be great … and I am sure you have a good reason for suggesting it.
<Bob> I would like to explore the concept of time-traps again because it something that many find confusing. Which is a shame because it is often the key to delivering surprisingly dramatic and rapid improvements at no cost.
<Lesley> Well doing exactly that is what everyone seems to be clamouring for so it sounds like a good topic to me. I confess that I am still not confident to teach others about time-traps.
<Bob> OK. Let us start there. Can you describe what happens when you try to teach it?
<Lesley> Well, it seems to be when I say that the essence of a time-trap is that the lead time and the flow are independent … for example the lead time stays the same even though the flow is changing. That really seems to confuse people … and me too if I am brutally honest.
<Bob> OK. Can you share the example that you use?
<Lesley> Well it depends on who I am talking to. I prefer to use an example that they are familiar with. If it is a doctor I might use the example of the ward round. If it is a manager I might use the example of emails or meetings.
<Bob> Assume I am a doctor then – an urgent care physician.
<Lesley> OK. Let us take it that I have done the 4N Chart® and the top niggle is ‘Frustration because the post-take ward round takes so long that it delays the discharge of patients who then often have to stay an extra night which then fills up the unit with waiting patients and we get blamed for blocking flow from A&E and causing A&E breaches‘.
<Bob> That sounds like a good example. What is the time-trap in that design?
<Lesley> The post-take ward round.
<Bob> And what justification is usually offered for using that design?
<Lesley> That it is a more efficient use of the expensive doctor’s time if the whole team congregate once a day and work through all the patients admitted over the previous 24 hours. They review the presentation, results of tests, diagnosis, management plans, response to treatment, decide the next steps and do the paperwork.
<Bob> And why is that a time-trap design?
<Lesley> Because it does not matter if one patient is admitted or ten … the average lead time from the perspective of the patient is the same – about one day.
<Bob> Correct. So why is the doctor complaining that there are always lots of patients to see?
<Lesley> Because there are. The emergency short stay ward is usually full by the time the post take ward round happens.
<Bob> And how do you present the data that shows the lead time is independent of the flow?
<Lesley> I use a Gantt chart, but the problem I find is that there is so much variation and queue jumping it is not blindingly obvious from the Gantt chart that there is a time-trap. There is so much else clouding the picture.
<Bob>Is that where the ‘but I do not understand‘ conversation starts?
<Lesley> Yes. And that is where I get stuck too.
<Bob> OK. The issue here is that a Gantt chart is not the ideal visualisation tool when there are lots of crossed-streams, frequently changing priorities, and many other sources of variation. The Gantt chart gets ‘messy’. The trick here is to use a Vitals Chart – and you can derive that from the same data you used for the Gantt chart.
<Lesley> You are right about the Gantt chart getting messy. I have seen massive wall-sized Gantt charts that are veritable works-of-art and that have taken hours to create … and everyone standing looking at it and saying ‘Wow! That is an impressive piece of work. So what does it tell us? How does it help?‘
<Bob> Yes, I have experienced that too. I think what happens is that those who do the foundation training and discover the Gantt chart then try to use it to solve every flow problem – and in their enthusiasm they discount any warning advice. Desperation drives over-inflated expectation which is often the pre-cursor to disappointment, and then disillusionment. The Nerve Curve again.
<Lesley> But a Vitals Chart is an ISP level technique and you said that we do not need to put everyone through ISP training.
<Bob>That is correct. I am advocating an ISP-in-training using a Vitals Chart to explain the concept of a time-trap so that everyone understands it well enough to see the flaw in the design.
<Lesely> Ah ha! Yes, I see. So what is my next step?
<Bob> I will let you answer that.
<Lesley> Um, let me think.
The outcome I want is everyone understands the concept of a time-trap well enough to feel comfortable with trying a different no-trap design because they can see the benefits for them.
And to get that depth of understanding I need to design a table top exercise that starts with a time-trap design and generates raw data that we can use to build both a Gantt chart and the Vitals Chart; so I can point out and explain the characteristic finger-print of a time trap.
And then we ‘test’ an alternative time-trap-free design and generate the prognostic Gantt and Vitals Charts and compare with the baseline diagnostic charts to reveal the improvement.
<Bob> That sounds like a good plan to me. And if you do that, and your team apply it to a real improvement exercise, and you see the improvement and you share the story … then that will earn you a coveted ISP Certificate of Competency.
<Lesley>Ah ha! Now I understand the reason you suggested this topic! I am on the case!