Assessing differences between simple slopes in simple slopes analysis

It is a standard practice to investigate moderation effects with two common analyses: moderated regression analysis examining interaction effects and simple slopes analysis examining individual simple slopes. However, existing research lacks clear explanations on how to assess and report differences between simple slopes in moderation analysis. Consequently, there is little research focusing on a difference between simple slopes as an effect size. This paper proposes a contrast analysis assessing the difference between simple slopes by evaluating whether their confidence intervals overlap. In addition, it reexamines the simple slopes reported in six articles published in business journals with the proposed contrast analysis. By incorporating the proposed contrast analysis alongside moderated regression analysis and simple slopes analysis, researchers can gain deeper insights into moderation effects. Thus, this paper recommends employing a combination of three analyses when examining moderation effects.