Add to ORKGOver the last 3 years the research I was involved in could for the most part be classified in terms of epidemiologic research design. This thesis does not discuss the intricacies of carrying out an epidemiologic study but rather describes the different applications of epidemiologic study designs including the advantages and disadvantages of each. With the ever-growing amount of literature, it is essential to understand the benefits and limitations of each type of study for clinical decision-making and for selecting the appropriate design when attempting to answer research questions. This thesis concludes by giving examples of different studies performed by the author that exemplify specific studies discussed in the introduction