A work breakdown structure is a very useful tool for any project manager, yet many do not know what it is. This article provides an overview of how a medical device work breakdown is created.  

If you would like to know more about creating a work breakdown structure for a medical device project, take a look at the video below. It is an excerpt from our online course Introduction to Project Management for Product Development of Medical Devices 

What is a medical device project work breakdown structure?

The WBS (work breakdown structure) is a hierarchical decomposition of the total scope of work to be carried out by the project team to accomplish the project objectives and create the required deliverables.  

The work breakdown structure organises and defines what should be included in the project. The work breakdown structure is often organised into multiple levels and displayed graphically.

A work breakdown structure is created by subdividing project deliverables and project work into smaller, more manageable components. The key benefit of this process is that it provides a structured vision of what has to be delivered.

Example of medical device work breakdown structure

The example above has been created using Microsoft Project. The typical tree structure of the WBS is visible as indentations of the work packages. The structure can also be deduced from the numbers in the WBS column. This WBS does contain elements that can be seen as different types of breakdown structures. See the section below. 

Other breakdown structures

It is also possible to create breakdown structures where you instead divide deliverables into groups based on other criteria, for example life cycle, product or organisational entities.   

When to create a work breakdown structure

A work breakdown structure is created early in the planning phase of a medical device project. The work breakdown structure should represent the work specified in the approved project scope statement.  

How to create a work breakdown structure

To create the medical device work breakdown structure, decomposition is used to break down the project into smaller, more manageable parts. 

Most work breakdown structures are created using project management software and indenting tasks to create summary tasks and work packages. This will create a project tree structure. 

The deepest part of a work breakdown structure should at most be four or five levels deep unless you have specific reasons to create more levels. Too many levels will make it difficult to effectively use the work breakdown structure for its purpose.  

The Practice Standard for Work Breakdown Structures book can be a helpful tool in putting together a work breakdown structure for the first time. 

Why should you have a work breakdown structure

Without a work breakdown structure, a Gantt chart would simply be a very long list of activities that must be completed. It is impossible to get an overview and manage hundreds of tasks in a list, nor is it possible to report costing to an appropriate level in the project or assign responsibilities.  

A work breakdown structure brings together tasks into work packages and summary tasks.  

Which software should you use for a work breakdown structure

For a graphical presentation of the work breakdown structure, you can use mind mapping software. One recommendation is Mindmanager which can export a mind map work breakdown structure to Microsoft Project with the click of a button.  

For a text-based work breakdown structure, Microsoft Project, Word or Excel are good alternatives. Here, you would typically indent text to create a hierarchical breakdown structure.  

Work breakdown structure template

If you can access a template from someone running a similar project within your organisation, you can get a head-start on your work breakdown structure.  

If you do not have access to one, you will need to create the work breakdown structure yourself. The good thing about this is that you can create a structure that works for you and your project. 

An example of a medical device work breakdown structure

One example of a work breakdown structure for a medical device project can be seen below.  

The product “Pre-Heart” is an imaginary device. It is a system for transporting donated hearts from a donor hospital to the transplantation hospital. It is made up of a transport box on the left-hand side and a disposable organ container on the right-hand side. 

Work breakdown structure tree

Life-cycle work breakdown structure

The first level of the breakdown consists of design, design verification, design transfer, design validation and close out. Even though some of these phases would be going on in parallel, they still, to some degree, represent life-cycle phases rather than deliverables.  

So, there is an element of life-cycle breakdown structure, and this is one way of creating a work breakdown structure.  

Traditional deliverable-oriented work breakdown structure

Looking at the next level, one can see the transport box along with labelling and the disposable. The transport box is broken down even further into mechanics, electronics, and software.  

This is a more traditional work breakdown structure which is deliverable-oriented and hierarchical in the sense that the transport box is broken down into two levels.  

A combination of work breakdown structures

In the design verification arm of this tree, the verification has been split up into subsystem verification of the disposable, software unit testing, and system testing which in turn is broken up into different types of testing.  

This work breakdown structure combines various types of breakdown structures in order to be as useful as possible in the project.  

Work breakdown structure and scheduling

The work breakdown structure is usually reiterated many times before it can be finalised. In fact, this structure is usually not completed until large parts of the schedule have been created. 

In the image below, the work breakdown structure is seen on the left-hand side in a project management software, and tasks such as design casing, design lid and design disposable have been added. 

Work breakdown structure example of pre-heart device

There are also logical relationships between the tasks so that they start when the previous task is finished. When you put in tasks and durations, it will give you new insights as to how you should structure your project. 

Based on this, it is quite clear that the work breakdown structure is closely tied in with the scheduling of activities. This is why it is a good idea to iterate the work breakdown structure until the medical device scheduling is completed.  

Would you like to know more about Project Management?

Take a look at our online Project Management for Product Development of Medical Devices course that provides a high-level overview as well as hands-on tools and techniques for developing a medical device within budget and schedule constraints. R&D engineers wanting to become project managers, consultants working with medical device projects, project managers within the medical device industry, and managers working directly or indirectly with projects and product development

We recommend that you take the Introduction to Design Control for Medical Devices online course prior to taking this course.

Peter Sebelius instructor

Peter Sebelius

Peter Sebelius is a highly esteemed trainer, consultant and entrepreneur in the medical device industry. He is a member of the Joint Working Group that is revising the ISO 13485 and ISO 14971 standards.

He has vast ‘hands on’ experience, having developed, amongst other things, a mechanical chest compression device and an ex vivo perfusion machine for lungs. He has received numerous awards including the Great Design Award and the title “This year’s specialist” by Veckans affärer.