Two common objectives in sport and exercise psychology research are to determinate if there is a relationship between two or more variables or if an intervention is effective or not (i.e., casual effects). Based on results obtained from a research study we are often eager to conclude that there are strong (or weak) evidence for the proposed relationship or intervention. This procedure might seem straightforward but there are several problems and critical issues that influence researcher’s assessments of the level of evidence. Unfortunately many researchers in the sport and exercise psychology field does not acknowledge these problems and critical issues when interpreting study results, which leads to flawed conclusions about the level of evidence (Ivarsson & Andersen, 2016). In this article we will: (a) highlight what we believe are some of the most critical issues in the sport and exercise psychology field for assessing the level of evidence, and (b) provide suggestions for how to deal with these issues.