Copying and handwriting ability in the screening of cognitive dysfunction in old age.

Geometric copying and handwriting tests are often assessed in the screening of cognitive deficiency in the elderly. The aim of the study was to show the regression of geometrical copying and handwriting with increasing cognitive impairment in old age. The study is population-based and includes 668 subjects aged 75 years and older, living in an inner-city area of Stockholm. The subjects were asked to copy a cube, two pentagons, a rhombus, two intersecting rectangles, and a circle. They were also asked to write a complete sentence spontaneously, a sentence from dictation and their name. Geometric copying and handwriting skills decreased in direct proportion to decreased cognitive functioning. The skills most sensitive to small changes in cognition were copying the cube and the pentagons. Other skills were less sensitive to small changes: writing a complete sentence, copying a rhombus, two rectangles and writing one's name. However, copying and handwriting appear to complement each other. Copying of the rectangles and rhombus is more useful than the other figures because these two can be discriminated throughout different stages of dementia. Sentence writing from dictation and signature can be used to evaluate severely impaired subjects because these skills seem to be retained longer than the spontaneous sentence writing.