In the early 1990s, Stefan Büchi was working on a research project at Imperial College London. He wanted to better understand the processes of change in patients with a chronic illness. He tried out new questionnaires and interview techniques. When these proved ineffective, he looked for other approaches. He suddenly had the idea that a simple, pictorial representation of the person and their illness could be helpful. The first patients responded very positively to working with the colored discs on a white background.

Thus, in collaboration with Prof. Tom Sensky, the prototype of a visual instrument called Pictorial Representation of Illness and Self-Measure (PRISM for short) was developed. During its use, he made the astonishing discovery: With PRISM, his patients could quickly talk about complex life stories – after just 5 minutes of instruction.

This tool has since been researched and described in more than 50 publications. In collaboration with experts from a wide range of disciplines, it is continuously being further developed and researched. Today, it enables hundreds of patients worldwide to collect, structure, and communicate their thoughts in a way never before possible. This helps them move forward.