Table 1.
Digital Clock Drawing Test Feature description.
| Variable Name | Variable Description |
|---|---|
| Total number of strokes | Total number of strokes used in drawing all components of this clock |
| Total completion time (sec) | Total time to draw all clock components |
| Clockface number of strokes | Total number of strokes used to draw the clockface |
| Clockface total time (sec) | Time to draw the clockface |
| Clockface overshoot distance (mm) | The minimum distance between start of the longest clockface stroke and the end, divided by the total length of the stroke. Gives a normalized measure of how far apart or overlapped the closest points near the end of the stroke are |
| Clockface overshoot angle (degrees) | Number of degrees between the start and end of the longest stroke in the first clockface, measured from the center of the ellipse. Positive: end of stroke goes past the start, negative: end does not go past the start |
| Hour Hand length (mm) | Distance from innermost to outermost point on the hand |
| Hour Hand distance from center (mm) | Distance from inner end of hour hand to center of ellipse |
| Hour Hand difference from ideal angle (degrees) | Difference between hour hand angle and the perfect angle |
| Minute Hand length (mm) | Distance from innermost to outermost point on the hand |
| Minute Hand distance from center (mm) | Distance from inner end of minute hand to center of ellipse |
| Minute Hand difference from ideal angle (degrees) | Difference between minute hand angle and the perfect angle |
| Hour Hand length/Minute Hand length | Represents the ratio of hour hand length the minute hand length |
| Post-Clock Face Latency (PCFL) (sec) | Delay between finishing the last stroke in the clockface and whatever is drawn next |
| Pre-First Hand Latency (PFHL) (sec) | Delay between whatever was drawn before the first clock hand and starting to draw that clock hand |
| Pre-Second Hand Latency (PSHL) (sec) | Delay between whatever was drawn before the second clock hand and starting to draw that clock hand |
| Total Drawing time (sec) | Total time with the pen drawing on the paper |
| Drawing length (mm) | Summation of total ink length of the drawn components |
| Average digit height (mm) | Average height of the bounding boxes for all numbers on the clock |
| Average digit width (mm) | Average width of the bounding boxes for all numbers on the clock |
| Average digit distance from circumference (mm) | Average distance from each digit to the nearest point on the clock face |
| Average digit misplacement (degrees) | A summation of each digit’s distance from ideal placement, divided by the number of digits |
| Clockface area (mm2) | Area of a circle fitted to the drawn clockface |
| Symmetry | Measure of how circular or oblong the clockface is, using horizontal and vertical dimensions |
| Velocity (mm/sec) | Drawing length/Drawing time |
| Average pen pressure | Average pressure of the pen on the paper during the entire test |
| Standard deviation of pressure | Standard deviation of pressure of the pen on the paper during the entire test |
| Average pressure/velocity | Average pressure/Velocity |
| Any digit missing | Any digits not appearing on the clock |
| Any digit outside | Any digits placed outside the clockface |
| Any digit perseveration | Any digits repeated |
| Anchoring | Anchoring |
| Any hand missing | Any of the hour hand or minute hand missing |
| More than one for each hand | More than one hour-hand or more than one minute-hand |
| Hand crossed Out | Any of the hands crossed out |
| Any digit over 12 | Any digits over 12 drawn |
| Ten-eleven stroke | Single line drawn connecting the numbers 11 and 2 |