Abstract: Objective: To offer a series of efficient methods for physiologists to make a scientific and rational experimental program. Methods: We bring about two questions as follows:Which are thecommon mistakesof statistics in the process of a physiological research? How to identify all the three essential factors? From the answers to these two questions, we highlight the methods to conduct a rigorous and accurate research design.Results: We summarized the special content of three essential factors in the experimental design:subject, influential factors, and effective indicators, which provide a basis for the design of the experimental program. Conclusion: In statistics studies, three essential factors which are "subject" "influential factors" "effective indicators" should be given considerable attention by the physiologists.

Key words: teenagers, heart sound, cardiac function, cardiac function classification, cardiac evaluation