I read that as .87 accuracy, .9 specificity (True Negative Rate). However, I can't find in the link provided in the article above the sensitivity (recall or True Positive Rate).
I'm guessing it goes a bit like this (assuming perfectly balanced classes which in reality they aren't):
Predicted + Predicted - Total
Actual + 378 72 450
Actual - 45 405 450
-------------------------------------
Total 423 477 900
Accuracy: 0.8700
Error: 0.1300
True Positive Rate: 0.8400
True Negative Rate: 0.9000
Precision: 0.8936
Recall (TPR): 0.8400
F-Score: 0.8660
I'm not sure how good or bad is 10% false positives and 16% false negatives are for that kind of diagnosis. The linked trial page says that 40% of diabetes patients have some degree of diabetic retinopathy (DR), that early treatment reduces vision loss "by as much as 52%" and that only some 50%-60% of people with diabetes have a yearly eye exam.Off the top of my head, it looks like automated screening will do some good and probably more good than harm, but without knowing how doctors judge good vs harm there's no way to know for sure how useful this device will really be.