Case-Control Studies

A well-designed randomized controlled trailed (RCT) is considered the gold standard for providing evidence regarding the effectiveness of novel interventions compared to standard approaches. However, there are situations where the RCT design is not possible or not appropriate. Firstly, when the outcome(s) of interest take a long time to occur (feasibility issues), and secondly when the outcome(s) involve potential harm to participants (ethical considerations). In these two situations the case-control design may be the most appropriate study design to answer the research question. This chapter provides a guide to readers on how to critically appraise a study that purports to be a case-control study.