Quality assurance of collected data is a significant part of the compilation process prior to publication of the Overseas Trade Statistics (OTS) and Regional Trade Statistics (RTS). Post-publication quality assurance is also conducted where potential anomalies are identified. The following content provides information on international and UK quality standards; how to challenge the published data, and how to access reports from past quality assurance activity. 
The OTS and RTS Quality Report, based on the GSS guidelines referred to below, is produced on an annual basis by the HMRC Trade Statistics Unit.

Quality Standards

To enable users to judge whether data outputs meet their needs, it is recommended that output providers report quality in terms of the output quality dimensions of the European Statistical System (ESS) which are defined in EU legislation.
The UK Government Statistical Service (GSS) also publish guidelines that contain a wide range of quality measures and indicators, grouped together using the six ESS output quality dimensions.
For international trade statistics these are further divided into more specific indicators of quality as detailed in the Eurostat (EU Statistical Office) DOC MET 1000 requirements. The quality of the OTS are judged against these indicators, in line with EU legislation.