in partial fulfil]ment of the - MSpace - University of Manitoba

adaptation ability from parents may verify night btindness (sommer et
â1., 1980). However, Vinton and Russell (1981 ) suggest that verification
of night blindness using a culturally based history may not be an
effective technique, as parents might not recognize night blindness in
their own children"
A decrease in dark adaptation ability (night blindness) is an indicator
of earLy hypovitaminosis À. This condition can be quantified by
dark adaptation testing. A Rapid Dark Àdaptation Test for adults, which
is inexpensive and easy to use under field conditions was described by
Thornton (1977), This Rapid Dark-Adaptation Test, however, rây not be
suitable for use with children, especially young children, since the
test requires cognitive skilts. À co-operative and attentive subject is
also required.
The focus of the current study is on the modification of the Rapid
Dark-Àdaptation Test (Thornton, 1977 ) and the development of a suitable
dark adaptation test for use with children, including young children who
are less than 5 year old.
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