This article presents the first version of a reporting format for modelling studies which is based on a general reporting format by our taskforce, which was published in the previous issue of this journal. The use of decision-analytical models for economic evaluations is increasing because, in practice, it is not always possible to derive information from prospective studies. However, the acceptance of modelling studies is generally lower than prospective studies not only because of the use of secondary data, but also because the reports of modelling studies do not always have sufficient transparency. Hence, a standardised reporting format may improve the transparency and, consequently, the acceptance of modelling studies. This article presents an example of a reporting format for economic evaluation based on modelling studies, which may facilitate the development of future guidelines for modelling studies. The format consists of a number of headings, which are followed by a brief recommendation on the content. This format does not deal with methodology and data management, but especially addresses validation and quality assurance, which may increase the transparency of the report.