Table 4. Odds ratio for SDF levels in study groups.

Level of SDF (%)	Men with ≥4% morphologically normal sperm cells, N (%)	Men with <4% morphologically normal sperm cells, N (%)	OR (95% CI)
0–15	133 (58.60)	68 (22.97)	0.2175 (0.1493–0.3170)**
16–30	83 (36.56)	131 (44.26)	1.3774 (0.9664–1.9632)
>30	11 (4.84)	97 (32.77)	9.5715 (4.9836–18.3829)**

**, highly significant difference between compared groups at P<0.0001. Chi² test. 95% CI, 95% confidential interval; N, number of subjects; OR, odds ratio; SDF, sperm DNA fragmentation.