1. Letter to the Editor
Boy or girl? – a new visual
acuity test screening tool
Tomoya Handa, Ran Nakadate,
Tomoko Hatayama, Tsukushi Yokota
and Nobuyuki Shoji
Department of Rehabilitation, Orthop-
tics and Visual Science Course, School
of Allied Health Sciences, Kitasato Uni-
versity, Sagamihara, Japan
doi: 10.1111/aos.12161
Editor,
M aking young children under-
stand the content of visual acu-
ity tests is not easy. For example, it can
be difficult to get them to understand
the visual acuity test targets on the
Landolt Ring chart or Snellen chart.
Eye charts for children that use simple
symbols as visual targets have been
reported, but the need to understand
the visual target itself has not changed
(Kastenbaum et al. 1977; Woodhouse
et al. 1992; Hered et al. 1997; Vision in
Preschoolers Study Group 2010). For
example, with the use of a picture
visual target, they need to understand
what the picture visual target itself is
(horse, car, etc.). Development of a
visual acuity test for screening that
young children can understand and
respond to in a short time and with lit-
tle difficulty is needed. We have devel-
oped and verified a new screening
visual acuity test for children.
The subjects are 308 eyes of 154 chil-
dren (5, 6 years old) who underwent a
trial in a preschool visual function
examination in the city of Sagamihara
(Kanagawa, Japan). Sagamihara con-
ducts that an ophthalmological exami-
nation is recommended for children
with visual acuity test results of <0.7
(decimal visual acuity). In a bright
room, a visual target was shown on a
32-inch TV monitor (TH-L32ET5, Pan-
asonic Corporation, Kadoma, Osaka,
Japan) and controlled by a PC using
software made by the authors. Subjects
sat at a test distance of 5.0 m, and their
eyes were measured one at a time. The
set-up for this screening visual acuity
test is shown in Fig. 1A. The visual tar-
get in this test is a hybrid image that is
set to look like a boy with visual acuity
of <0.7 (decimal visual acuity) and to
look like a girl with visual acuity of
‡0.7 (decimal visual acuity). The visual
target for this test is shown in Fig. 1B.
The line thickness of the girl’s hair and
ribbon is set at 2 mm for a visual angle
of 0.0247° at a test distance of 5 m.
The contrast of the lines for the hair
and ribbon was set at 53% based on
previous verification. Visual acuity test
results with the Landolt C chart are
also divided into two levels of ‡0.7
(decimal visual acuity), and <0.7 (deci-
mal visual acuity), with the results of
the present screening visual acuity test
and the visual acuity test with a Lan-
dolt C chart (uncorrected visual acuity)
then compared. This study followed
the tenets of the Declaration of
Helsinki, and all subjects provided
informed consent.
The rate of agreement between the
results with this screening visual acu-
ity test and the visual acuity using a
Landolt C chart was 72.1% (agree-
ment in 222 of 308 subject eyes) when
evaluated based on the two levels of
visual acuity, ‡0.7 (decimal visual acu-
ity) and <0.7 (decimal visual acuity).
All the children were able to under-
stand the test with a simple explana-
tion, and the test could be carried out
over a short time period of about 10–
20 seconds for each child.
With the visual target in this screen-
ing visual acuity test, children could
easily understand the test when they
were simply asked, ‘Do you see a
boy?’ or ‘Do you see a girl?’. In addi-
tion, with the use of a TV monitor to
display the visual target, children nat-
urally gaze at even a distant visual
target. Based on these two advanta-
ges, it is thought that this screening
visual acuity test for children could be
carried out over a short period of time
without difficulty, so that this test
may be widely applicable for use in
the visual acuity tests of children.
References
Hered RW, Murphy S & Clancy M (1997):
Comparison of the HOTV and Lea sym-
bols charts for preschool vision screening. J
Pediatr Ophthalmol Strabismus 37: 24–28.
Kastenbaum SM, Kepford KL & Holmstrom
ET (1977): Comparison of the STYCAR
and Lighthouse acuity tests. Am J Optom
Physiol Opt 54: 458–463.
Vision in Preschoolers Study Group (2010):
Effect of age using Lea symbols of HOTV
for preschool vision screening. Optom Vis
Sci 87: 87–95.
Woodhouse JM, Adoh TO, Oduwaiye KA,
Batchelor BG, Megji S, Unwin N & Jones
N (1992): New acuity test for toddlers.
Ophthalmic Physiol Opt 12: 249–251.
Correspondence:
Tomoya Handa, CO, PhD
Department of Rehabilitation
Orthoptics and Visual Science Course
School of Allied Health Sciences
Kitasato University
1-15-1 Kitasato, Minami-ku
Sagamihara 252-0373
Japan
Tel: + 81 42 778 9671
Fax: + 81 42 778 9684
Email: thanda@kitasato-u.ac.jp
(A) (B)
Fig. 1. (A) Setting for the screening visual acuity test. The visual target in this screening visual
acuity test is displayed on a TV monitor at test distance of 5.0 m. The examiner covers one eye
of the child being tested with an occluder and measures the unilateral visual acuity of the right
eye followed by the left eye in that order. (B) The visual target for the screening visual acuity
test. This visual target is a hybrid image, which looks like a girl if the ‘ribbon’ and ‘hair’ are
recognized and looks like a boy if the ‘ribbon’ and ‘hair’ are not recognized.
Acta Ophthalmologica 2013
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