Clinical research either directly involves a particular person or group of people or uses materials from humans such their behavior or samples of their tissue. It can involve epidemiological and behavioral research, health services research and patient-oriented research like drug trials or accuracies of diagnostic tests. It is a series of steps that lead from question to answer. There is an organized structure by which we formulate questions, develop methods to gather information and answer clinical problems. The purpose of organizing the structure is to allow studies to be repeated and validated by other researchers. There are several research designs, and the choice should be influenced by the main objective of the research. The methodology is the manner of collection of data that will give confidence in the results and conclusion. This requires identifying all sources of bias and uncertainty, and developing a method that can minimize them. Actual data collection can be obtained by inspecting the records, by conducting interview or physical examination or laboratory/ imaging investigations, or by a combination of these data-eliciting methods. Lastly, the final report should be concise but contain all the details in relation to the objective of the research. The format of the written report depends on the methodology and the requirement of the journal where it is intended to be published.