00   Mother\'s education:                                                             Primary vs. vocational                   000 vs. 000   0.00   0.00--0.00    NS    Primary vs. secondary                    000 vs. 000   0.00   0.00--0.00    NS    Primary vs. university                   000 vs. 000   0.00   0.00--0.00    NS   Father\'s education:                                                             Primary vs. vocational                   000 vs. 000   0.00   0.00--0.00    NS    Primary vs. secondary                    000 vs. 000   0.00   0.00--0.00    NS    Primary vs. university                   000 vs. 00