BMC Public Health 2008, 8:136 http://www.biomedcentral.com/1471-2458/8/136 Table 5: Cox Proportional Hazards Regression Analysis by Gender: Selected Demographic and Community Factors Independent Variables *Educational level Primary Secondary or higher Age **Economic status Middle class High class Urban location Southern region 3.02 5.43 1.16 0.99 0.97 0.77 1.44 Hazard Ratio p-value Hazard Ratio 95% C.I. p-value Males 95% C.I. 1.36 – 6.71 2.58 – 11.44 1.04 – 1.29 0.69 – 1.44 0.62 – 1.50 0.55 – 1.07 1.07 – 1.95 0.01 < 0.001 0.01 0.97 0.88 0.12 0.02 1.00 1.32 1.09 0.90 0.79 0.85 1.71 Females 0.49 – 2.03 0.71 – 2.44 0.96 – 1.23 0.61 – 1.31 0.49 – 1.27 0.58 – 1.25 1.22 – 2.40 1.00 0.38 0.19 0.58 0.33 0.41 0.01 *Referent group was those with no formal education. **Referent group was those in the low economic class. experienced in our study; figures that are consistent with other Nigerian studies [16-21]. The NDHS, with its national coverage, provides a more reliable portrait of adolescent sexual behaviours than small-scale reports. Our figure for females 15 to 19 years old who were sexu- ally active (22.2%) is much lower than the retrospective report of 20–24 year olds in the NDHS 75.4% of whom reported having had sex before the age of 20. That figure, however, failed to disaggregate the ever from never mar- ried youth. As reported by the NDHS, 56% of young peo- ple 20–24 years were married by the age of 20 years. Thus, married adolescents accounted for a large proportion of Table 6: Cox Proportional Hazards Regression Analysis by Gender: Demographic, Community, and Psycho-social Factors Independent Variables Males Females Hazard Ratio 95% C.I. p-value Hazard Ratio 95% C.I. p-value Demographic factors *Educational level Primary Secondary or higher Age Stronger opinion on importance of religion **Economic Status Middle class High class Psycho-social factors Use of alcohol Supportive attitude to adolescent delay of sexual debut Perceived higher FP access More positive attitudes to family planning More positive about community support for condom use More positive about condom efficacy Higher condom access Gender attitude HIV prevention knowledge Sexuality communication Community factors Higher radio exposure Higher television exposure Urban location Southern region *Referent group was those with no formal education. **Referent group was those in the low economic class 2.16 2.32 1.00 1.07 1.01 0.89 1.90 0.36 1.03 1.19 1.05 1.28 1.42 0.95 0.90 0.97 0.90 1.29 0.70 1.20 0.81 – 5.77 0.91 – 5.92 0.89 – 1.13 0.63 – 1.82 0.67 – 1.52 0.54 – 1.50 1.38 – 2.62 0.25 – 0.52 0.97 – 1.09 1.09 – 1.31 0.99 – 1.12 1.07 – 1.53 1.14 – 1.76 0.89 – 1.02 0.79 – 1.02 0.90 – 1.06 0.65 – 1.23 0.87 – 1.91 0.49 – 1.01 0.87 – 1.65 0.12 0.08 0.97 0.81 0.96 0.66 < 0.001 < 0.001 0.29 < 0.001 0.13 0.01 0.01 0.15 0.09 0.53 0.49 0.21 0.57 0.27 1.31 1.08 0.95 0.59 0.83 0.67 0.90 0.38 1.02 1.18 1.02 1.24 1.18 1.13 1.08 1.00 0.92 0.99 0.90 1.38 0.44 – 2.91 0.49 – 2.39 0.82 – 1.10 0.37 – 0.94 0.53 – 1.30 0.38 – 1.18 0.51 – 1.60 0.25 – 0.57 0.95 – 1.09 1.07 – 1.30 0.95 – 1.09 1.05 – 1.46 0.96 – 1.45 1.04 – 1.23 0.96 – 1.22 0.90 – 1.10 0.64 – 1.31 0.64 – 1.52 0.59 – 1.36 0.93 – 2.05 0.78 0.85 0.48 0.03 0.40 0.17 0.71 < 0.001 0.58 0.01 0.675 0.01 0.11 0.01 0.19 0.93 0.64 0.96 0.60 0.11 Page 10 of 14 (page number not for citation purposes)