Table 1: Basic characteristics of study subjects.

Group I 95% CIGroup II 95% CI
NumberPercentLowerUpperNumberPercentLowerUpper

Mother literacyPrimary/secondary12059.752.766.727568.463.772.9
High school6029.923.936.39824.420.428.6
University2110.46.514.9297.24.79.7

Father literacyPrimary/secondary13466.760.773.625362.958.067.9
High school4220.914.926.98922.117.926.1
University2512.48.017.46014.911.718.4

Mother jobHousewife18190.086.194.037092.089.394.5
Employed2010.06.013.9328.05.210.7

Family income (per month, US $)Less than 40012964.257.770.124560.956.265.7
400–8005627.921.434.313934.629.639.3
More than 800167.94.511.9184.52.76.5

Type of marriageFamilial5627.921.933.815438.333.643.5
Nonfamilial14572.166.278.124861.756.566.4

Mean(95% CI)Mean(95% CI)

Mother age29.14(28.24–29.97)27.87(27.34–28.41)
Father age33.47(32.51–34.42)33.61(33.04–34.17)