Table 2. Distribution of qualitative variables as frequency and percentage.

DR: diabetic retinopathy; NPDR: non-proliferative diabetic retinopathy; PDR: proliferative diabetic retinopathy

Distribution of qualitative variables
Gender	Male n (%)	Female n (%)	P-Value
Non-diabetics	12 (60.0%)	8 (40.0%)	0.937
Diabetics without DR	13 (65.0%)	7 (35.0%)
Diabetics with NPDR	11 (55.0%)	9 (45.0%)
Diabetics with PDR	12 (60.0%)	8 (40.0%)
Hypertension	Yes	No	P-Value
Non-diabetics	0 (0.0%)	20 (100%)	< 0.001*
Diabetics without DR	11 (55.0%)	9 (45.0%)
Diabetics with NPDR	15 (75.0%)	5 (25.0%)
Diabetics with PDR	16 (80.0%)	4 (20.0%)
Cardiovascular disease	Yes	No	P-Value
Non-diabetics	0 (0.0%)	20 (100%)	0.228
Diabetics without DR	2 (10.0%)	18 (90.0%)
Diabetics with NPDR	4 (20.0%)	16 (80.0%)
Diabetics with PDR	3 (15.0%)	17 (85.0%)