Quality Improvement Methods
53. Value Stream Map
a. Definition: A map or diagram which displays not only the sequence or flow of processes, such as the process map described in Section 36, but also includes "value" as it is defined within the Lean method. Value is work done that is desired by the customer (patient) versus non-value added work or waste that is not desired by the patient, such as waiting or redundant processing. Based on a process map the time taken for each step, such as registration at a doctor's office visit, is included as a set of value-added time and non-value-added times. Totals of these times across the entire map provide the overall proportion of these two types of times. The intent is to create a picture of where opportunities exist for improvement. If a QUERI research project envisioned a new set of tasks, the value stream map (VSM) might be a good way to look at how close the plan is to an optimal one.
An additional virtue of the value stream map above the process map is that it is even better as a discussion tool. Since it numerically highlights where the greatest waste is, it directs the discussion towards the largest opportunity for improvement.
- Rother, Mike; Shook, John (2003). Learning to See: value-stream mapping to create value and eliminate muda. Brookline, MA: Lean Enterprise Institute. ISBN 0-9667843-0-8.
- Jimmerson, Cindy, and Amy Jimmerson. Value stream mapping for healthcare made easy. Productivity Press, 2009.
- Lummus, Rhonda R., Robert J. Vokurka, and Brad Rodeghiero. "Improving quality through value stream mapping: a case study of a physician's clinic." Total Quality Management 17.8 (2006): 1063-1075.
c. Example: The VSM is often drawn with a separate horizontal timeline showing the value and non-value time. This map can also be used to identify problems and opportunities for improvement. Such as:
Similarly, a value stream map can be used to assure all the time taken to do interviewing or other data gathering during research can be assessed to identify non value added elements which should be reduced or eliminated. Researchers have found this method is perhaps best used before much data gathering has been done, and can shorten the data gathering phase and improve the quality of results. Other benefits from such analysis can be improvements to the data gathering design such as better metrics or opportunities for redesign. See Ullman, Fredrik, and Roman Boutellier. "A case study of lean drug discovery: from project driven research to innovation studios and process factories." Drug discovery today 13.11 (2008): 543-550.
1) Identify all processes in the sequence of interest and develop a process map (see Section 36). Of particular importance, those developing the map should start with observing the current practices, perhaps spending significant time to do so. This assures that the map will be accurate and all important real problems identified.
2) Determine the value added (VA) and non-value added (NVA) times for each process
3) Draw the VSM and calculate the overall proportion of value added and non value added for the entire process mapped.
4) As with the process map, validate the map with the staff now working with the process being mapped.
5) Identify problem areas on the map.
6) Analyze the results regarding the proportion of NVA time, which is the extent of the opportunity for improvement
7) Determine changes to reduce the NVA times and, of course, implement them.