Josephine van Dongen

Chapter 4 106 the anticipated ten percent), despite substantial effor ts to keep parents of par ticipants engaged in completing questionnaires and repor ting AGE. The multiple and complex health issues that many parents of a MRC child encounter during infancy may be barriers to full engagement in an observational study like ours. Mean follow-up however, was at least one year after vaccination (14.5 months). A Cox model takes observation time into account and was adjusted for several covariates, thereby minimizing bias resulting from differential loss to follow-up. Conclusion In this population of infants with MRC and prolonged care, administration of at least one dose of HRV implied insignificant protection against severe rotavirus AGE.The findings are in contrast with the general rotavirus VE estimates for healthy infants and underline the impor tance of conducting separate studies on vaccine performance in specific populations.