Growing together: An analysis of measurement transparency across 15 years of player motivation questionnaires

[Preprint Version] There are many questionnaires available to assess player motivation, originating from a diverse range of disciplines. Each discipline differs in their usage and reporting of questionnaires, but there has been no attempt to synthesise their application or create a standard way of using them. No standard approach leads to a lack of transparency in reporting their usage, which affects the ability of the field to build on one another. This has made it unclear whether player motivation research is a unified research community, or a collection of individuals with a similar goal. This work assesses the transparency of questionnaire reporting practices in papers published in the last 15 years of player motivation research (n=238). Overall, there is a lack of transparency in reporting questionnaires, driven by a lack of priority in presenting items alongside text. Many papers use questionnaires that are based on theory or have been used to measure specific factors in the past, but explicit justification is rare. This work concludes with a checklist for authors to use to ensure questionnaire reporting is transparent, so that the field can standardise and allow for more cohesive research synthesis.