Once the prototype was ready, it was time to test it with real people. We wanted to understand one thing above all: were the letters genuinely clear and easy to use?
To do this, we conducted in-person, one-to-one interviews. This approach gave us the space to explore each person’s experience in detail and to see how they worked through the information without influence from others. It also meant that we could place printed copies of the letters directly in people’s hands and observe how they engaged with them in a setting that closely reflected real life.
We recruited participants through pop-up sessions in libraries across South Wales, which worked well for three reasons. Firstly, libraries are familiar, accessible places with regular footfall, which helped us reach a broad mix of people quickly. Secondly, this approach helped us hear from people who might not usually volunteer for research, but who are still part of the audience for these letters. And finally, running sessions in areas with different levels of deprivation gave us a useful way to capture a range of reading abilities, which was especially important when testing written communication.
In total, we spoke to 21 people from a broad mix of backgrounds, including participants with accessibility needs and people who spoke English as an additional language.
So, what did the interviews teach? Overall, feedback was positive. People consistently told us the letters were clear and contained all the information they needed. But they also highlighted opportunities to further improve the reader experience, which fell into three themes:
Make the letter easier to scan. Participants generally understood the information, but some felt the letter could be shorter and easier to move through. They pointed to opportunities to reduce blocks of text, improve signposting and add more spacing—changes that would help people process the information more quickly, especially those with dyslexia or other accessibility needs.
Make key information stand out. Participants wanted the most important details - such as NHS numbers, appointment times and contact information - to be easier to spot. They also shared some clear suggestions: information about what to do if you cannot attend should appear earlier and be repeated, the NHS number should sit next to the patient’s name, and the appointment time should come before the location.
Plan for wider accessibility. Participants also highlighted two longer-term needs: clearer travel information for people unfamiliar with the location or relying on public transport or support from others, and digital versions of the letters for people who use phones or assistive technology to access information.
Using feedback we gathered during user research, we made four major changes in the second iteration of the letters.
We duplicated the help pathways, showing them in two places in the letter. We added a block of contact information in the upper right corner and repeated it (with some additional context explaining why someone may need to use a help pathway) directly underneath the appointment details.
Next, we switched the ‘At’ and ‘On’ information. As one research participant said, “it doesn’t matter where the appointment is, if I’m not free when it is”.
In the lower half of the letter, we added additional subheadings to assist readers in skimming the text and picking up what is important to them.
Finally, we advanced the first iteration’s work to improve readability by increasing the font size and line spacing even more throughout. To do this we rearranged and cut down the contextual language to leave only what’s essential.
The new design will soon be deployed. We already know that by reducing the letter from 2 sheets of paper to 1, we’ll save 4p per letter. If we match the number of letters sent last year, that’s a saving of £41,599.48.
However, it's likely to be far higher than that. Hywel Dda has now joined other health boards in using WIS to send vaccination letters and as the number of letters sent increases, so will the savings.
We’ll also monitor benefits delivered from other areas, such as:
A reduction in people calling or emailing for support with their vaccination appointment
An increase in attendance to vaccination appointments
But the lasting impact of this project goes beyond cost savings. By developing a clear, inclusive and compassionate design approach for bilingual appointment letters, shaped and tested by the people who receive them, we have a reusable blueprint that prioritises user need alongside efficiency.