This review aimed at comparing these studies and to elaborate the relevance and reduction of exacerbations rates by LABA, LAMA and ICS application through effect size calculation by means of Cohens’ d. These studies display a common pattern. The reduction of exacerbation rates is only being achieved for less severe exacerbations (Cohens’ d max. ). For more severe exacerbations and for the comparison of different substances Cohens’ d remains below , indicating that the effect of the medications is practically irrelevant. The impact of LABA’s, LAMA’s and ICS on exacerbation rates in COPD patients is obviously overrated.