The video above demonstrates the use of FHS digitial pen data. The FHS collects digital pen recordings of written responses to the neuropsychological test protocol. This includes digital pen data collected from the digital clock-drawing test involving participant manually drawing clocks and the results being graded. This is similar to the traditional, hand-scored test but uses a special pen and paper to record the actual process as a file without a video. The unique digital pen is equipped with a camera sensor that records real-time pen motion by capturing its time-stamped XY coordinate position relative to specialized marked paper. Machine learning algorithms have been developed to calculate meaningful clock scores based on this information, capturing many clock drawing features that may be too subtle for a human researcher to detect.
Since the clock-drawing test is stored this way, the participants' process can be exactly recreated in a program. This is by the use of specialized digital clock drawing data files stored in the CSK file format. They document detailed stroke-by-stroke depictions of clock drawing tests. The CSK format contains a metadata section summarizing the contents, followed by timestamps and XY coordinate pairs that detail the position of the pen at all times. This allows the entire process to be analyzed and the data to be in some cases directly viewed.
The ClockSketch software is used to replay the entire clock drawing process, from the initial strokes to the completed image. There are also menu options to customize for playback and analysis. The image can be filtered based on the copy version, command version, or both. Playback can recreate the entire clock drawing process without physical presence in the testing room. By replaying the sequence as many times as needed, subtle nuances in the participant’s actions may be detected.