The digital transformation of higher education demands effective and efficient methods for learning assessment. Research has shown that tests have the potential to be an appropriate medium not only to diagnose learning success but to improve learning outcomes/processes in general. In this study, we examine possible connections between the use of digital tests and learning success. Based on a survey (n=71) and a quantitative analysis (n=214) with logging and exam assessment data, we find three points that indicate positive correlation: Firstly, students perceive digital tests as motivating and useful. Secondly, we detect a positive relation between the points students achieved in the online tests and the exam results (Spearman correlation coefficient of 0.39), and thirdly, students who participated continually in the digital testing system on average succeeded and passed the exam. The results show the importance of systematic digital testing in learning management systems, but also the need for more research with respect to other contexts and domains.