Table 4 Comparison of gender distribution among ON patients.

	Male, number (%)	Female, number (%)	OR (95% CI)	F test (p)
Controls	110 (44.0)	140 (56.0)	2.133 (1.224 to 3.713)	0.008
ON patients	21 (26.9)	57 (73.1)
Controls	110 (44.0)	140 (56.0)	4.845 (2.02 to 11.589)	0.0002
ON (MS+) patients	6 (14.0)	37 (86.0)
Controls	110 (44.0)	140 (56.0)	1.048 (0.518 to 2.118)	1
ON (MS−) patients	15 (42.9)	20 (57.1)
ON (MS+) patients	6 (14.0)	37 (86.0)	4.625 (1.586 to 13.396)	0.0053
ON (MS−) patients	15 (42.9)	20 (57.1)