Frailty-Based Competing Risks Model for the Analysis of Events in Transition to Adulthood

The analysis of clustered time-to-event data is carried out using random effects models, popularly known as frailty models in the literature of event history analysis. The present work demonstrates an application of competing risks frailty model for analysing adulthood transitions that are clustered into geographical regions. Observations from the same cluster are assumed to be correlated because these usually share certain unobserved characteristics. Ignoring such correlations may lead to incorrect standard errors of the estimates of parameters of interest. Besides making the comparisons between usual competing risks model and competing risks model with frailty for analysing geographically clustered time-to-event data, important demographic and socio-economic factors that may affect the duration of transition to adulthood events namely: transition from leaving study to work and/or marriage of Indian youths are also reported in this paper. The data from the study "The Youth in India: Situation and Needs 2006-2007" which was implemented by the International Institute for Population Sciences, Mumbai and the Population Council, New Delhi (IIPS and PC 2010), is used. The results of the analysis highlight the significant transition differentials among Indian youths by gender, place of residence, religion, caste, wealth quintile, among others. We found that after leaving study men join the work much earlier than women, and prefer to postpone their marriage. But women have higher likelihood of entering into marriage early compared to men. Rural residents have significantly higher likelihood of joining work and lower likelihood of entering into marriage compared to their urban counterparts at their early age. Wealth quintile has been observed to have a mild or no significant effect on the hazards of adulthood transitions.