Steps for testing a mediation model. (A) First, a simple linear regression analysis is performed to determine whether age significantly predicts the speech recognition measure. (B) Second, a simple linear regression analysis is performed to determine whether the mediator measure of interest predicts the speech recognition measure. (C) Third, a simple linear regression is performed to determine whether age predicts the mediator measure of interest. Finally, a multiple linear regression analysis is performed, now with both age and the mediator as predictors of the speech recognition measure. A full mediation effect of the mediator would be evidenced by a significant effect of the mediator, but now a nonsignificant effect of age. A partial mediation effect of the mediator would be suggested by a decline in the β value for age when the mediator is added to the model.