Specifications
Each card of the Cardiff Acuity Test measures approximately
20 by 27 cm. A set comprises 12 acuity levels (36 cards) and
is supplied in a portable carry case with full instruction manual.
The following table gives the acuity levels for two working
distances.
| |
Acuity at 1m |
Acuity at 50cm |
| Card |
picture |
LogMAR |
Metres 6/ |
Feet 20/ |
LogMAR |
Metres 6/ |
Feet 20/ |
| LVA |
apple |
1.2 |
96 |
320 |
1.5 |
192 |
640 |
| LVB |
sock |
1.1 |
76 |
253.4 |
1.4 |
152 |
506.6 |
| A |
fish |
1.0 |
60 |
200 |
1.3 |
120 |
400 |
| B |
house |
0.9 |
48 |
160 |
1.2 |
96 |
320 |
| C |
boat |
0.8 |
38 |
127 |
1.1 |
76 |
253.3 |
| D |
train |
0.7 |
30 |
100 |
1.0 |
60 |
200 |
| E |
duck |
0.6 |
24 |
80 |
0.9 |
48 |
160 |
| F |
car |
0.5 |
19 |
63 |
0.8 |
38 |
126.7 |
| G |
fish |
0.4 |
15 |
50 |
0.7 |
30 |
100 |
| H |
train |
0.3 |
12 |
40 |
0.6 |
24 |
80 |
| I |
boat |
0.2 |
9.5 |
32 |
0.5 |
19 |
63 |
| J |
car |
0.1 |
7.5 |
25 |
0.4 |
15 |
50 |
| K |
duck |
0 |
6 |
20 |
0.3 |
12 |
40 |
| L |
house |
-0.1 |
4.8 |
16 |
0.2 |
9.5 |
32 |
| M |
train |
-0.2 |
3.75 |
12.5 |
0.1 |
7.5 |
25 |
The following table shows expected values for acuity in children
with normally developing vision. These figures are taken from
a study with a large population of children aged 1 to 3 years
carried out in Cardiff by Dr. Maggie Woodhouse and colleagues.
Note that the norms were produced using an earlier version of
the Cardiff test, in which the highest acuity recordable at
1m was 6/6 (20/20). The latest version incorporates a higher
acuity (6/3.8, 20/12.5); it is feasible that children in the
older age group will attain this acuity.
| Age (months) |
Binocular Acuity(Snellen equivalent) |
Monocular Acuity(Snellen equivalent) |
| |
Metres (6/ ) |
Feet (20/ ) |
Metres (6/ ) |
Feet (20/ ) |
| 12 – 17.9 |
48 – 12 |
160 – 40 |
48 – 15 |
160 – 50 |
| 18 – 23.9 |
24 – 7.5 |
80 – 25 |
30 – 7.5 |
100 – 25 |
| 24 – 29.9 |
15 – 7.5 |
50 – 25 |
19 – 7.5 |
63 – 25 |
| 30 - 36 |
12 – 6 |
40 – 20 |
12 – 6 |
40 – 20 |
Supportive literature
Adoh TO, Woodhouse JM. (1994). The Cardiff Acuity Test used
for measuring visual acuity development in toddlers. Vision
Research 34, 555-560.
Adoh TO, Woodhouse JM, Oduwaiye KA. (1992). The Cardiff Test:
a new visual acuity test for toddlers and children with intellectual
impairment. A preliminary report. Optometry & Vision Sciences
69, 427-432
Fariza E, Kronheim J, Medina A, Katsumi O. (1990). Testing
visual acuity of children using vanishing optotypes. Japanese
Journal of Ophthalmology. 34, 314-319
Frisen L. (1986). Vanishing optotypes. New type of acuity test
letters. Archives Ophthalmology 104, 1194-1198
Geer I, Westall CA. (1996). A comparison of tests to determine
acuity deficits in children with amblyopia. Ophthalmic &
Physiological Optics 16, 367-374
Jackson AJ, Saunders KJ. (1999). The optometric assessment
of the visually impaired infant and young child. Ophthalmic
& Physiological Optics 19, S49-S62
Johansen A, White S, Waraisch P. (2003) Screening for visual
impairment in older people: validation of the Cardiff Acuity
Test. Archives Gerontology & Geriatrics 36, 289-293
Jones D, Westall C, Averbeck K, Abdolell M. (2003). Visual
acuity assessment: a comparison of two tests for measuring children's
vision. Ophthalmic & Physiological Optics 23, 541-546
Woodhouse JM, Adoh TO, Oduwaiye KA, Batchelor BG, Megji S,
Unwin N, Jones N. (1992). New Acuity Test for toddlers. Ophthalmic
& Physiological Optics 12, 249-251
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