Table 2. The proportion of successful and unsuccessful surgery by ethnicity and hole size.

Ethnicity	Hole size
	<250 microns	250–400 microns	>400 microns	Total
Failed surgerya
Caucasian	1	1	6	8
Afro-Caribbean	0	2	9	11
Asian	0	0	5	5
Total	1	3	20	24
Successa
Caucasian	22	42	38	102
Afro-Caribbean	3	8	13	24
Asian	1	12	20	33
Other	0	0	2	2
Total	26	62	73	161
Success rate (N=185)
Caucasian	95.70%	97.70%	86.40%
Afro-Caribbean	100%	80%	59.10%
Asian	100%	100%	80%

^aComplete data available on 83.3% (185/222) cases.