Table 1.

Comparison of Mean±SD of Log Urinary 17U/17X Ratio Based on Country of Residence, Gender, and Smoking Habit among Healthy Ethiopian Volunteers Using Independent t-Test

Parameters	n	Range	Coefficient of variation	Mean±SD	Difference between means	95% CI for the mean difference	P
Geographic differences
Living in Ethiopia	99	−0.35 to 0.64	169%	0.12±0.26	−0.034±0.03	−0.097 to 0.029	0.29
Living in Sweden	72	−0.42 to 0.70	144%	0.15±0.22
Gender differences
Female	69	−0.42 to 0.70	173%	0.12±0.20	−0.02±0.03	−0.087 to 0.040	0.47
Male	102	−0.34 to 0.61	148%	0.14±0.24
Smoking habit
Smokers	19	−0.42 to 0.70	155%	0.14±0.22	−0.01±0.05	−0.11 to 0.09	0.78
Non-smoker	152	−0.22 to 52	158%	0.13±0.23

One outlier with very low 17U/17X ratio was excluded. The result was not changed with or without exclusion of this outlier.