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New paediatric contrast test: Hiding Heidi low-contrast 'face' test
1Department of Optometry, National University of Malaysia, Kuala Lumpur, Malaysia. aihong@medic.ukm.my
Background:
The Hiding Heidi low-contrast 'face' test is a new paediatric contrast test to evaluate the ability to detect objects with low contrast. The purpose of the present study was to compare the Hiding Heidi low-contrast 'face' test (HH) with the Pelli-Robson contrast sensitivity test (PR) and the functional acuity contrast test (FACT) in the low-contrast assessment.
Methods:
Thirty university students participated in the present study. The contrast ability was evaluated by using three different methods: HH, PR and FACT. The HH was repeated on two separate occasions to test the repeatability.
Results:
There was a significant positive correlation between HH and PR (r = 0.65, P < 0.01); between HH and FACT at 6 cycles per degree (c.p.d.; r = 0.64, P < 0.01); between HH and FACT at 3 c.p.d. (r = 0.91, P < 0.01); and between HH and FACT at 1.5 c.p.d. (r = 0.56, P < 0.01). The paired t-test showed a significant difference between HH and PR (t = -6.05, P < 0.01); between HH and FACT at 6 c.p.d. (t = -11.16, P < 0.01); between HH and FACT at 3 c.p.d. (t = -8.35, P < 0.01); and between HH and FACT at 1.5 c.p.d. (t = -5.64, P < 0.01). They had good agreement. The HH had a high repeatability.
Conclusions:
The HH had a positive correlation but produced significantly different readings when compared with FACT and PR. The features and role of HH in clinical contrast sensitivity assessment are discussed.
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