Correct planning should be carried out to control the design & development of your medical device however, many companies fall short when it comes to their documentation and overall approach to planning.

In the second of this two-part blog, Senior Design Engineer, John and Human Centred Designer, Amber continue to address some frequent questions regarding writing a design & development plan as well as the typical activities involved.

Is there any early design & engineering work involved?

A big chunk of the work in the early phase of the project is often identifying what needs to be characterised, what needs to be optimised and therefore, what needs to be verified?

Characterisation can involve things which are outside of your control. For example, with an injector pen we know to expect back pressure from when the needle enters somebody’s arm. However, this isn’t something you can easily control, it’s a natural phenomenon which needs consideration. Or perhaps the glassware or bung detail is not fully understood, it could be a number of details which need to be fully understood.

This could be something which needs to be fully characterised, calculated and accounted for before key decisions can be made or specific work can commence. This is the kind of activity that might require some ideation and broad-brush design as well as some engineering and maths modelling to really understand what needs to be characterised, what needs to be verified and what can be optimised so that you can plan and account for specific tasks / sub-tasks. You may need to take a broad-brush design and begin CAD modelling it to understand it at a feature level in 3D form so that you can plan for these individual features in the development plan.

Generally, it’s likely that you will be doing some design and engineering activity at this stage but, this will be outside of design controls. Instead, it’s likely to be quick design sprints on problem areas, using the most efficient tools to better your understanding of the device or problem you’re trying to solve to form the most accurate plan, with as few assumptions as possible.

Can you make assumptions in the development plan?

It’s fine to make assumptions however, you must be mindful that with too many major assumptions, the plan risks becoming largely inaccurate which will ultimately cost time and money further into the development. Where possible, it’s better to control assumptions as much as possible from the offset to form a more accurate plan.

In particularly for projects where the values are high, if your estimate of work is out by a margin of 10-20% for example, this is a large sum so it’s worth investing the time into developing a fully detailed and accurate development plan to prevent budgetary and technical difficulties affecting key milestones and final delivery.


Alongside your flowchart and other documentation, you will be writing the top level development plan:

While you’re developing and using the flowchart to map and determine what needs to be done, you will be writing the high-level development plan. The purpose of this document is a top-level document that key decision makers are going to be analysing to allocate budgets and choose development partners etc. There’s an art to writing these documents and remaining concise! The design development plan should follow a loose structure of;

Again, this would be a live document that you will be writing alongside your flow chart, Gannt chart and other supporting documentation. Essentially, this is the launch pad to those documents so you would list them as external references. This is the master document that governs all of those documents and will provide all of the supplementary documentation for example, your proposal, the Gannt chart which would include the flow chart and any initial work that you’ve done alongside for example, a feasibility study.

So, this is the high-level master documentation which executives can read to understand how much it’s going to cost, how long it’s going to take and if it will be feasible. Then, if they’d like to dig deeper, they can begin analysing that supplementary documentation.

In a big company, there would likely be a head of a department i.e. head of design development (there could be multiple of these for various devices / elements) – they would typically ask an external consultant or, one of their team to determine whether this project is worthwhile investing in – it’s that person who would typically come to the likes of Haughton Design to ask us to do the work.

The design development manager would be typically looking at this higher-level plan while their executive will solely be looking at the first page and key details i.e. time and cost.

Typically, a pharma company will take this document, process it through their financial system to govern the financials to understand return of investment and market share. They will then plan it into the budget for the next financial year to decide on whether the estimated budgets are accurate and whether the project should move forward.

Tools to form the plan:

At HD we typically use Excel flow charts to begin with. The software used is not defined by regulations, you can use whatever works best for you. During early sprints, we’re typically doing quick sketches in brainstorming sessions, early CAD work in SolidWorks or some Simulation work such as motion or FEA studies.

It’s important to have a QMS system in place. Depending on your budget, resource, and scale of project(s), you can build or buy a QMS system. For start-ups on a lean budget, we might recommend the likes of Qualio. For larger companies, who are handling a number of device development projects, examples such as GreenlightGuru or Aligned Elements might be a better solution.

Who would you involve to form a new product or medical device development plan?

We would recommend involving a variety of people throughout the process of writing the development plan:

The Client and possibly the Drug Developer as well as Clinicians / Experts in the condition & therapy

They are typically the expert on their product, industry and business so they hold a lot of information and valuable insight.


We would also involve the most relevant expert consultants in the sector too – these are people that have a wealth of experience in the specific industries.

Key Manufacturers and Suppliers

Where possible, we would also involve the identified key suppliers and manufactures for the project. Typically, large projects are under strict confidentiality therefore we’re unable to share enough information to gather accurate quotes and advice. However, major suppliers will form a large part of the cost so, it’s useful to gather as accurate costs as possible through sharing rough idea of part counts and features.

Test Houses

Test houses – those that will be undertaking the characterisation and verification work which you may not be able to undertake inhouse. These will also be significant factors for timescales and costs so may need to be booked well in advance.


Typically, we would involve the full team at HD to advise during the development of the plan as the activities it requires will involve everyone working on them at some point during the possible 2/3 years of the device development, so their inputs and experience provides a key insight to forming an accurate plan.

Please reach out if you would like to learn more about how we could help form your medical device development plan.

Amber Davies - Human Factors Design Engineer & Marketing Manager at Haughton Design Amber Davies 5 April 2022


Get in Touch with Amber Davies

Human Factors Design Engineer & Marketing Manager

Amber graduated from Cardiff Metropolitan University with a degree in Product Design. She has a particular interest in the medical field stemming from her personal experience of using a medical device. She pairs her design background with her personal experiences to apply empathy and develop improved user experiences. Amber also combines this understanding to liaise with customers and create digital content at HD.

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