To better estimate patient satisfaction, we developed a two-dimensional face scale to improve on the one-dimensional face scale. A major reason for doing this was to evaluate negative feelings which are often underestimated since Japanese patients are reluctant to express such feelings.
Using more than 300 responders, we conducted a comparison of our original one-dimensional written scale (Scale A), a one-dimensional face scale (Scale B) and a two-dimensional face scale (Scale C). The results showed feelings of dissatisfaction with Scale C were significantly less than for Scale A and B and there was no significant difference between Scale A and B in this respect. In addition, over 80% of the responders favored Scale C from an accuracy point of view but for simplicity Scale B was preferable, and this was so for responders of all ages.