Period-Cohort Effects Models for Sexual Debut in Namibia

  • Lillian Pazvakawambwa University of Namibia
  • Lawrence Kazembe University of Namibia
  • Nelago Indongo University of Namibia
Keywords: sexual debut, discrete time-to-event models, Namibia


Early sexual debut is often associated with a number of social challenges. However, the hazard and risk factors of changing pattern of age at first sex have not been fully explained.  This paper investigated the period-cohort effects by fitting flexible time-to-event models of sexual debut using retrospective cross-sectional data of the 2000 and 2006-7 Namibian Health and Demographic Survey, to establish individual and structural effects, and simultaneously investigated spatial frailty effects, non-linear effects of age, cohort and period on the timing of sexual debut among women. The hazard of sexual debut reduced as the woman’s year of birth increased suggesting a generational effect. The North Eastern parts of Namibia were associated with a higher risk of early sexual debut compared to all other regions. Intervention strategies should be multifaceted and involve not only schools and communities but individual family units as they have a bigger role to play in this regard

Author Biographies

Lillian Pazvakawambwa, University of Namibia
Department of Statistics and Populations Studies15
Lawrence Kazembe, University of Namibia
Multi-Disciplinary Research Centre
Nelago Indongo, University of Namibia
Multi-Disciplinary Research Centr