Abstract
We investigate the performance of QuantiScale, a new multi-touch interaction technique for the quantification of distances in medical images and discuss the benefits and prospects of redesigning interactions with multi-touch devices. Taking advantage of the multi-touch capabilities, QuantiScale behaves like a tape measure, but automatically adjusts the view onto the measured object to improve precision and speed. The technique has been studied in a real-world scenario measuring the diameter of structures for the diagnostic reading of medical images and provides hints for the replacement of traditional mouse-based interaction with gestural interaction. Results of the quantitative evaluation indicate a high measurement precision particularly for small objects. Participants experienced QuantiScale as being more fun, natural, and intuitive in comparison to mouse-based interaction even though the subjective preference for speed and precision was still in favor of the mouse.