Modelling a cluster randomised controlled trial to evaluate the impact of a cash incentivised prevention intervention to reduce teenage pregnancy among high school learners in rural KwaZulu-Natal, South Africa.
A third of adolescent girls fall pregnant before the age of 20 in South Africa, and this happens despite contraceptives and condoms being free and mostly accessi- ble. This thesis aims to evaluate the impact of a cash conditional incentivised preven- tion intervention on teenage pregnancy through the use of appropriate statistical methods that take into account the clustering effect as well as the binary nature of the response variable. This thesis will focus on the analysis of interim data of the study which was collected at baseline and first follow up. Fourteen schools were allocated to two study arms (intervention and control arm), totalling to 1412 teenage girls who were followed up annually for 3 years. Partic- ipants in the intervention arm received the conditional cash transfers while those in the control arm did not. The intervention arm comprised of 704 girls while the control arm had 708 girls at baseline. The null hypothesis for this study states that there is no difference in the rate of pregnancy across the study arms. Urine specimen were collected to test for pregnancy. Baseline data analysis revealed an overall pregnancy proportion of 3.47% with that of 2.84% and 4.10% respectively for the intervention and control arm. These findings together with all the other findings from the applied statistical methods yielded insignificant results thus, favoring the null hypothesis. Amongst the covariates used, age and grade were multi-collinear. In all the fitted models, the age variable was statistically signif- icant (p<0.01) which is indicative that this variable plays an important role in pregnancy. From this study, a total of 280 (approximately 21%) girls missed a follow up visit. No statistical analysis was done to account for the missing data as the study was analysed at an interim thus, there is a possibility that participants might miss a particular visit but return for another scheduled visit. Based on the outcome obtained from the interim data analysis, it is evident that teenage pregnancy oc- curs regardless of treatment arm thus, we conclude that cash conditional transfers does not exclusively prevent teenage girls from falling pregnant.