Having found a button phobic who was willing to work with me I began to send her photographs of buttons in order to gauge her response to a range of buttons. Some of these (below) I asked her to put into order of repulsion so that it might be possible to discover a pattern- in terms of colour, size, design and material. (The numbers on the photos are mine for identification rather than her order.)
I sent images rather than the real thing in order that her reaction displayed revulsion rather than fear (a distinction explored in the paper: Disgust and a Specific Phobia of Buttons by Lissette M Saavedra Ms. and Wendy K Silverman Phd. (Publ J.Am.Acad.Child adoles. Psychiatry Nov 2002).
I then called her and she put them in order. With other photographs of specific buttons, she wrote on them and sent the photo back. I have now started to make pictures based on her response.