Ramalingam Sitharthan, Deepthi Gilla


The choice of the study design is a major determinant of scientific quality and clinical value of a research study. To select an appropriate study design is a perplex task for novice as well as veterans in research. AYUSH systems of medicines have evidence database showing the effectiveness in a wide range of clinical conditions, yet improving the quality of trials by well- designed studies is indispensable to demonstrate widespread utility on more scientific grounds. This article describes the structured classification of research designs done on the basis of a selective literature search concerning medical research. The study design and type that can best answer the particular research question at hand must be determined not only on a scientific basis, but also in view of the available resources, ethical issues and practical feasibility of study.

Keywords: Study design, Clinical trial phases, Observational studies, Experimental studies. Randomized Controlled Trial (RCT).

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