Compared with the control cluster , at the 6-month follow-up assessment , the intervention cluster had a significantly higher proportion of correct answers to queries about human immunodeficiency virus/acquired immunodeficiency syndrome ( HIV/AIDS ) ( standardised coefficients of multiple linear regression ( B ) 0.047 ; P = 0.020 ) and awareness of places providing free contraceptives ( odds ratio [ OR ] 2.011 , 95 % confidence interval [ CI ] 1.635-2 .472 ; P < 0.001 ) , and a significantly lower proportion accepting premarital sex ( OR 0.492 , 95 % CI 0.416-0 .582 ; P < 0.001 ) , practising premarital sex ( OR 0.539 , 95 % CI 0.478-0 .608 ; P < 0.001 ) or suffering from gynaecological disorders ( OR 0.801 , 95 % CI 0.697-0 .921 ; P = 0.002 ) .