Correction: Opportunities and challenges for real-world studies on chronic inflammatory joint diseases through data enrichment and collaboration between national registers: the Nordic example
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Chatzidionysiou K, Hetland ML, Frisell T, *et al*. Opportunities and challenges for real-world studies on chronic inflammatory joint diseases through data enrichment and collaboration between national registers: the Nordic example. *RMD Open* 2018;4:e000655.

The 13th author’s name has been corrected to ‘Bjorn Gudbjornsson'.

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