Table 1.

Relationship between visual impairment and RTA

Visual acuity	History of RTA		Total (%)
	Yes (%)	No (%)
6/18	2 (50)	9 (90)	11 (78.6)
6/24	2 (50)	0 (0)	2 (14.3)
6/36	0 (0)	1 (10)	1 (7.1)
Total	4 (100)	10 (100)	14 (100)

chi-square = 5.982, df = 2, p = 0.050