According to Donald Kirkpatrick's The Four Levels Approach, which of the following is measured by improvement in bottom-line results such as sales, quality, customer satisfaction, safety, employee morale, turnover, costs, and profits? According to Donald Kirkpatrick's The Four Levels Approach, which of the following is measured by improvement in bottom-line results such as sales, quality, customer satisfaction, safety, employee morale, turnover, costs, and profits? Application Satisfaction Impact Learning