Discussion
In both groups, there was a significant difference between the results of the pre-test and the post-test. This difference was to be expected since all participants had taken part in continuing education during the course. This result reflects the increase in knowledge during the course period. The IG who used the game app had increased knowledge, as did the CG, proving that learning with the serious game seems to have a positive effect as the conservative scripted learning that supports the general course content such as lectures and seminars. However, we cannot measure the effect of the scripts and the game because all students also attended lectures and seminars which also have an impact on the learning effect.In both years, there was no significant difference between the two groups' data on the pre-test. It appears that both groups had similar pretest knowledge. There was also no significant difference between the two groups on the post-test results in either year. Based on these results, the null hypothesis is accepted. Both groups appear to be similarly prepared for the post-test. However, it also shows that learning with the app performs as well as learning with the paper scripts, as mentioned earlier. The results are consistent with the literature [However, the significant difference in the first year (Van Gaalen et al. (2021) describe that increased use of learning materials generally indicates repetition. This is one of the strongest variables affecting memory, leading to better learning outcomes and retention [What is striking about the data is that the second cohort shows poorer results than the first cohort in both the pre- and post-tests. They appear to represent a weaker learning group, but their results show similar learning trends to those of the first group regardless of learning type (CG or IG).The participants enjoyed using the app and had fun learning. They rated it as good and motivating. This seems to be the main benefit of implementing serious gaming. However, it must be kept in mind that rewarding a previously unrewarding activity such as learning factual knowledge, can lead to a shift from intrinsic to extrinsic motivation [The positive evaluation of the students in our study may be due to the fact that the students were involved in the creation of the app and their wishes and requirements were taken into account during the development. The app was optimized for their needs. Particular attention was paid to simple, intuitive operations with an appropriate amount of information that does not overwhelm the students. This perception is also supported by Aboalshamat et al. (2020), who suggests in a study that the amount of information and its complexity are important factors in achieving the desired improvement through gamification [The participants stated that they did not feel well-prepared by the app for the final exams relevant to their studies. One reason could be that students have theoretical and practical exams, and thus not only pure factual knowledge but also application tasks are tested. We should have differentiated this question into practical and theoretical exams since the app only trains the theory of low taxonomy. We should also consider improving the question format in the app so that students feel prepared for questions with higher taxonomy.The number of games and questions played are proof of the app's acceptance. On average, each student played 351 quiz questions. However, we know from the evaluation that some participants did not use the app at all (Based on the evaluation data, we can assume that the gaming behavior of the participants was very different. On the one hand, there seem to be enthusiastic players who used the app at least once a day (15%) and on the other hand, more than half of the participants played at least once a week (51.5%). This shows that the participants have different needs, and the app seems unsuitable for everyone as a learning medium. Why some participants did not use the app could not be explained from the evaluation. One reason could be that the control group received the app late in the course and they were already in the learning phase for the course-relevant exams and therefore did not want to switch to the app. This statement was at least noted on isolated evaluation forms and is therefore only a thesis and not proven. Another reason could be that these students generally do not like to play with their cell phones or prefer to learn in other ways. A query about mobile gaming behavior in the evaluation questionnaire would have been helpful for interpretation.As for books, the literature shows that some students prefer to learn with books rather than ebooks or other digital alternatives. A University of California study showed that most 390 students still prefer to read their academic texts in print if they want to achieve a deep learning outcome [The strength of our study is its design as a randomized intervention trial. The knowledge level of both groups was assessed before the intervention. The app was studied in different phases. Not only was student acceptance determined, but objective testing was conducted, usage data was tracked, and the validated System Usability Scale was used to assess the app's utility in detail.The limitations of the current study are the small number of cases, the untraceable use of paper scripts, and the lack of comparison with exams relevant to the study. Our study only shows the results of a small number of students over two consecutive years at one site. This is not generally representative, so further studies large numbers of students should be conducted in a multicenter design. Due to rigorous privacy data regulations, we were unable to correlate app usage data with study-relevant exam scores. It was also not possible to record the use of the paper scripts or this could only have been done based on the students' statements, which led to an enormous bias in the actual tracking of the app usage data and thus would not have yielded any reliable statements. In addition, pre-test and post-test were not mandatory for passing the course and were unannounced, which could imply a lower level of engagement in preparing for the tests.We would like to mention that it is essential to involve all groups in developing and producing an application to make it a success. It is important to create the necessary personnel and technical conditions and to keep an eye on the cost–benefit ratio. If these prerequisites are met, we can only recommend implementing such a project.The use of the game has achieved a high level of acceptance among students and teachers. Therefore, further technical developments and an expansion to other courses and faculties are planned. In addition, an implementation of new question types, the integration of video data and questions of higher taxonomy and game modes such as "duel" will take place and the possibility of creating questions by students themselves will be integrated. Perhaps we could achieve even better results with the app if the gamification character of the app were strengthened. In particular, competition and scoring seem to positively impact learning [