Article 11 — Quality requirements and quality reporting

1. Member States shall take the necessary measures to ensure the quality of the data sets and metadata transmitted, by assessing and monitoring: (a) the quality of the data sources used; (b) the exhaustiveness and accuracy of the population covered in accordance with Article 3(6), in particular with regard to hard-to-reach population groups. 2. Member States shall ensure that the data obtained using the sources and methods set out in Article 8 give an accurate estimate of the population in accordance with Article 3. Coverage quality of data on the basis of Article 3(6) shall be confirmed and thoroughly described by Member States in accompanying metadata and quality reports pursuant to paragraph 6 of this Article. Member States shall use the estimation methods carried out for total population at national level in accordance with Article 3(6), point (b), and described in the quality reports, to adjust all data sets for the detailed topics the person’s basic characteristics, the person’s socioeconomic characteristics and the person’s household situation, prepared on the basis of sources referred to in Article 3(6), point (a). Member States may use those estimation methods for further detailed breakdowns. For that purpose, Member States may use a dedicated adjustment category. 3. For the purposes of this Regulation, the quality criteria referred to in Article 12(1) of Regulation (EC) No 223/2009 shall apply. 4. Member States shall take appropriate and effective measures to: (a) establish frames that are fit for the purposes of this Regulation and that may be used for the purposes of Article 12 of Regulation (EU) 2019/1700; (b) avoid possible risks of undercounting or double counting related to the free movement of persons in the Union and, to the extent possible, to the access of persons to cross-border services linked to vital events and to the rights of persons to buy cross-border, own and use housing property across the Union, by using, inter alia, single digital identifiers; (c) avoid possible risks of undercounting or double counting and ensure better comparability of migration flows. 5. The Commission (Eurostat) shall assess the quality of the metadata on the specifications and of the data transmitted with a view, inter alia, to publishing them in a user-friendly manner on the Commission (Eurostat) website. 6. Member States shall transmit to the Commission (Eurostat), for the first time by 31 December 2030, and subsequently by 31 December of every year that ends with a 0, 3 or 7, a quality report describing the quality of the statistics provided and the statistical processes for the data sets provided during the relevant period. Those quality reports shall include information on the data sources and methods used, the application of the concepts and definitions and related possible effects on quality of the selected data sources, the data revisions and their reasons and impacts, and the statistical disclosure control methods. The quality reports shall also detail how Member States have applied the measures referred to in paragraph 1 and how the quality criteria referred to in paragraph 3 have been met. 7. The Commission shall adopt implementing acts setting out the practical arrangements for, and the content of, the quality reports referred to in paragraph 6 of this Article. Those implementing acts shall not impose a significant additional burden or cost on Member States. They shall be adopted in accordance with the examination procedure referred to in Article 17(2). 8. Any major adaptation provided for by the implementing acts referred to in paragraph 7 of this Article may be the subject of financial and technical support pursuant to Article 14 or subject to a derogation pursuant to Article 18. 9. Member States shall inform the Commission (Eurostat) as soon as possible of any relevant information or changes with regard to the implementation of this Regulation that would influence the quality of the statistics provided and shall, in the event of a negative effect on the quality of those statistics, take action to resolve the issue without undue delay. 10. Upon a duly justified request by the Commission (Eurostat), Member States shall provide, without undue delay, necessary additional clarifications for the purpose of evaluating the quality of the statistical information, such as the assessment results of the data sources and the documentation of methods.