TABLE 1.

Level of simulated impairment used in this study.

Level	How simulated	Mean visual acuity logMAR (ETDRS)	Mean contrast sensitivity logCS (MARS)
Habitual	No simulation	−0.04 ± 0.17	1.78 ± 0.06
Level 1	Four layers of 258	0.52 ± 0.17	0.83 ± 0.11
Level 2	Five layers of 258	0.72 ± 0.16	0.65 ± 0.13
Level 3	Six layers of 258	1.03 ± 0.14	0.40 ± 0.15
Level 4	Seven layers of 258	1.30 ± 0.13	0.15 ± 0.11
Level 5	One layer of 256	1.61 ± 0.09	0.01 ± 0.03
Level 6	One layer of 253	1.96 ± 0.10	0.00 ± 0.01
Level 7	Visual field approx. 5–9° (Timmis et al., 2021), but VA and CS remain habitual.