The developmental eye movement (DEM) test and Cantonese-speaking children in Hong Kong SAR, China.
BACKGROUND
There is no published norm for the Developmental Eye Movement (DEM) Test for Cantonese-speaking Chinese children. This study aimed to determine the normative values of this test for Cantonese-speaking Chinese children in Hong Kong SAR and to compare the results with the published norms of English-speaking and Spanish-speaking children.


METHODS
Cantonese-speaking students aged from 6 to 11 years were tested by the DEM test in Cantonese and a digital recorder was used to record the process. The DEM scores for the 305 students were determined by listening again to the audio records after the test and computed by using the formula from the DEM manual, except that the 'vertical scores' were adjusted by taking the vertical errors into consideration. The results were compared with other norms that have been published.


RESULTS
Our subjects made more vertical errors than in other normative studies and adjusted vertical scores were proposed. In both adjusted vertical and horizontal scores, the Cantonese-speaking children completed the tests much faster than the norms for English- and Spanish-speaking children, the differences of the means being significant (p < 0.0001) in all age groups.


CONCLUSIONS
The DEM norms may be affected by differences in languages, cultures and education systems among different ethnicities. The norms of the DEM test are proposed for Cantonese-speaking children in Hong Kong SAR, China.
Pang
Peter C
PC
School of Optometry, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, China.
Lam
Carly S
CS
Woo
George C
GC
D000367:Age Factors; D002648:Child; D002657:Child Development; D015331:Cohort Studies; D005133:Eye Movements; D006723:Hong Kong; D006801:Humans; D007802:Language; D012016:Reference Values