The relative risk of severe visual loss for black patients vs nonblack patients was 3.5 in at least 1 eye and 4.8 in both eyes.

• 黑人病患相较于非黑人病患发生严重视力缺损的相对风险，至少一眼如此的风险为3.；5、两眼都发生该情况的风险为4