Overview of Clinical Research Study Designs Using Examples From the Swallowing Literature

Study designs have numerous advantages and disadvantages that must be considered when addressing a research question, hypothesis, and objective. These include but are not limited to cost, feasibility, and ethical concerns. This review describes common study designs from the dysphagia literature with corresponding relevant examples for each design type. Further, discussion of the main differences between descriptive and analytical, qualitative and quantitative, observational and experimental, and retrospective and prospective study designs is provided. Specific aspects of various study designs, including matching, randomization, and blinding are also discussed. Finally, the importance of working closely with experts, such as epidemiologists and biostatisticians, in the early stages of research to assist with selection of the most appropriate study design and development of the research protocol is strongly recommended.