Health Technology Assessments (HTAs) are gaining importance with support of governments in the Western World. With evidence synthesis and economic modeling gaining in accuracy and complexity, there is an increasing demand to assess the quality and validity of the data used for these studies. In keeping with the trend of the "Big Data" explosion, "Real World Evidence" is being seen as the answer to getting HTAs to the next level of accuracy. Hence there is the need for better tools to document and process "Real World Data". Registries have been existing for more than half a century now. However; their use was primarily done for epidemiological research. This article discusses how with the turn of the century, registries have evolved from being just portals for enrolment of patients to being highly sophisticated tools for economic modeling and cost analysis. We also discuss the challenges faced in optimal utilization of registries and how they can be addressed by better designing and implementation. We also discuss some policy decisions which have been taken to ensure that registries will continue to evolve and be a very important tool in HTAs.

The art of predicting the results of any drug treatment has always been a topic of interest among the scientific community across the globe. Many diseases have been attributed to gene defects, giving rise to a whole new field of pharmacogenomics within the domain of clinical pharmacology. Stratified medicine is the science of associating such diseases with genetic defects and predicting the efficacy or toxicity of a particular drug treatment. The article provides an overview of how stratified medicine got evolved and its current and future clinical implications. It also explains how "companion diagnostics" play a crucial role in the success of stratified medicine along with its complex economics, pricing and reimbursement issues.