Table 2

Frequency and extent of misgrading of 49 digital images of diabetic retinopathy with JPEG compression

Degree of error (grades)		Degree of JPEG compression
Degree of error (grades)		90%	80%	70%	0%
+1			3	2

0	29	33	35	39
−1	15	15	9	7
−2	2		2	1
−3	3	1