Assessing the effectiveness of digital game-based learning: Best practices

• Questions regarding current assessment practices of DGBL.
• Best practices for effectiveness assessment of educational games are defined.
• Interviews with experts in pedagogy/psychology were conducted.
• Areas for improvement and suggestions for improvement are defined.
• More systematic approach for effectiveness assessment in this field is recommended.

In recent years, research into the effectiveness of digital game-based learning (DGBL) has increased. However, a large heterogeneity in methods for assessing the effectiveness of DGBL exist, leading to questions regarding reliability and validity of certain methods. This has resulted in the need for a scientific basis to conduct this type of research, providing procedures, frameworks and methods that can be validated. The present study is part of a larger systematic process towards the development of a standardized procedure for conducting DGBL effectiveness studies. In a first phase, the variety in methods that are used for sampling, implementation of the interventions, measures and data analysis were mapped in a systematic literature review using Cochrane guidelines. The present paper reflects the second stage, where this variety in elements are presented to experts in psychology and pedagogy by means of semi-structured interviews, in order to define preferred methods for conducting DGBL effectiveness studies. The interview was structured according to five dimensions that were used in the literature review: 1) participants (e.g., characteristics of the sample involved) 2) intervention (e.g., contents, format, timings and treatment lengths, intervention(s) in control group(s)) 3) methods (sampling, assignment of participants to conditions, number of testing moments) 4) outcome measures (e.g., instruments used to measure a certain outcome) and 5) data-analysis. The interviews were transcribed and analyzed using qualitative software package nVivo. Our results show that areas for improvement involve the intervention dimension and the methods dimension. The proposed improvements relate to implementation of the interventions in both the experimental and control group, determining which elements are preferably omitted during the intervention (such as guidance by the instructor, extra elements that consist of substantive information) and which elements would be aloud (e.g., procedural help, training session). Also, variables on which similarity between experimental and control condition should be attained were determined (e.g., time exposed to intervention, instructor, day of the week). With regard to the methods dimension, proposed improvements relate to assignment of participants to conditions (e.g., variables to take into account when using blocked randomized design), general design (e.g. necessity of a pre-test and control group) test development (e.g., develop and pilot parallel tests) and testing moments (e.g., follow up after minimum 2 weeks). In sum, the present paper provides best practices that cover all aspects of the study design and consist of game specific elements. While several suggestions have been previously made regarding research design of DGBL effectiveness studies, these often do not cover all aspects of the research design. Hence, the results of this study can be seen as a base for a more systematic approach, which can be validated in the future in order to develop a standardized procedure for assessing the effectiveness of DGBL that can be applied flexibly across different contexts.