COVID testing - a case study in LEAN. A while ago I went for a COVID test due to a local outbreak of the virus. The queue was long and moved slowly so I was curious as to how long each test really took. The whole process consisted of just two steps, a registration, to record some personal information, and the swab test itself. The times were 5 mins for the registration and 0.5 mins for the test, with a wait time of 2 mins between each step.
So value-add (the test itself) was 7% of the total cycle time for one test. The process throughput was limited by the longest cycle time in the value stream (the registration) to just 12 people per hour, resulting in the long queue outside the testing building. This was NOT the fault of the people working the process, as they were all busy doing what they had been told to do, but rather a fault in the process itself.
Whilst the above process may not be typical and may have already improved with use, it illustrates the importance of considering the timing of a process as well as its function, especially where throughput is important. During the process design, a run through to collect typical times for each step would have immediately shown up its limitations, and countermeasures could then have been put in place to improve the flow.
For example, the registration asked a number of questions of which only 20% were probably necessary at the time, given that the vast majority of people being tested would test negative (currently 99.9% across AU) and would not be contacted again other than to be sent their test results via SMS. Application of the 5-whys test would have clarified which questions were absolutely necessary and which could be removed, in order to decrease the cycle time.