CRUZ C. answered • 04/25/19
Ph.D. in Applied Management and Decision Science, Info Sys Management
Generally speaking, you would not calculate both a Pearson product-moment correlation coefficient and a regression equation on the same variables in one study. The Pearson product-moment correlation coefficient measures the direction and strength of a relationship, if any, between variables or many variables without knowing precisely how or why they are related or without knowing the functional relationship. Whereas in regression calculations, the regression equation can show many different types of functional relationships and is used to to predict an outcome. Regression involves cause and effect. Correlation does not speak to cause and effect. However, in epidemiology BOTH the Pearson Product-moment correlation coefficient and simple regression analysis are used to test the strength of association between exposure to disease and outcome. In observational epidemiological studies, testing for associations requires regression analysis rather than the use of the Pearson product-moment correlation coefficient.
