Clock-drawing test performance in the normal elderly and its dependence on age and education.
OBJECTIVE
The main objective was to assess the relative frequency and types of errors on the clock-drawing test (CDT) in normal elderly subjects, and the dependence of their CDT performance upon their age and education.


METHODS
The CDT performance of 242 normal elderly subjects, stratified according to age and education, was analyzed using both an absolute error count and a modified scoring sheet derived from 2 scales.


RESULTS
Normal elderly subjects (average age: 73.4 +/- 8.4 years; mean Mini-Mental State Examination score: 27.7 +/- 1.6) often have problems placing figures on the clock face and differentiating the clock hands correctly. The absolute number of errors increases with age and decreases with formal school education. A cumulative effect of both high age and a low level of school education yields substantially inferior scores, on the modified scale used, in comparison with younger subjects and those with higher levels of education.


CONCLUSIONS
The frequent errors made by normal elderly subjects, and a combined negative influence of high age and low education level, suggest caution when interpreting the significance of CDT performance in the elderly.
von Gunten
Armin
A
Service Universitaire, Département de Psychiatrie, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland. armin.von-gunten@chuv.ch
Ostos-Wiechetek
Marzanna
M
Brull
Juliette
J
Vaudaux-Pisquem
Ines
I
Cattin
Sylvie
S
Duc
René
R
D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000523:psychology*; D003072:Cognition Disorders / Q000175:diagnosis / Q000523:psychology; D004522:Educational Status; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests / Q000592:standards; D011597:Psychomotor Performance; D012016:Reference Values; D013557:Switzerland