Analysis of statistical data is an important part of any medical writer’s skill set, especially those professionals working in publication and regulatory areas. Under - standing the various study designs is key to a thorough understanding of study methodology. Nevertheless, many medical writers come from a non-clinical background and have a knowledge gap when it comes to study design options. This article describes the main types of study design. Case report, cross sectional, case control, cohort, quasi experimental, randomised controlled trials, and systematic reviews and meta analyses studies are explained and their uses, advantages, and limitations discussed.