Quality data is typically considered from the concepts in ISO8000 or from the FAIR principles. In general, both aim to ensure that data is in fact representative of what is supposed to represent and that it can be found and used by those who require it. Neither concept provide numerical definitions of quality nor rules for implementation, only guidelines and suggestions. Therefore a numerical evaluation of data quality is difficult due to various implementation and interpretation. Work is ongoing to find trusted and comparable routes to measuring data quality.