A toothache is a pain in or around a tooth that may be caused by: 1  Tooth decay. 2  Abscessed tooth. 3  Tooth fracture. 4  A damaged filling. 5  Repetitive motions, such as chewing gum or grinding teeth.
A correlational study determines whether or not two variables are correlated. This means to study whether an increase or decrease in one variable corresponds to an increase or decrease in the other variable.
Purpose of Correlational Research. (cont.) â¢ The variable about which the prediction is made is. called the criterion variable. â¢ Both scatterplots and regression linesare used in. correlational studies to predict a score on a criterion. variable. â¢ A predicted score is never exact.