Contrast sensitivity comparisons for Pelli Robson, Hiding Heidi and Double Happy tests
Reviewed by Fiona Rowe

The authors aimed to compare contrast thresholds and measure agreement across current paediatric assessment of contrast sensitivity with Hiding Heidi and Double Happy contrast sensitivity tests vs. the gold-standard Pelli Robson chart. Reduced contrast levels were similar under different light and vision conditions. The study included 50 adult volunteers aged >18 years with no ocular abnormalities. Mean age was 24.5 ±7.98 years with binocular visual acuity of -0.04 ±0.09logMAR. Mean visual acuity of the weaker eye was -0.01 ±0.09 and this eye was used for testing. In defocused conditions with normal bright light, the weaker eye measurement was 0.47 ±0.09log. A ceiling effect was found for Hiding Heidi; 94% reached the maximum score. A ceiling effect was suggested for the Double Happy test but just 18% reached the maximum score. Baseline log contrast sensitivity was 1.7 ±0.1, 1.88 ±0.09 and 1.94 ±0.11 in bright conditions, and -0.21 ±0.1, -0.04 ±0.11 and -0.21 ±0.14 in dim conditions, for Pelli Robson, Hiding Heidi and Double Happy tests respectively. There was a strong positive correlation for the Pelli Robson and Double Happy test but not for Pelli Robson and Hiding Heidi test.

Comparison of current paediatric contrast sensitivity assessments using simulated reduced contrast thresholds.
Morillo PA, Milling A, O’Connor A.
STRABISMUS
2023;31(3):182–7.