RT Journal Article SR Electronic T1 Correction: Opportunities and challenges for real-world studies on chronic inflammatory joint diseases through data enrichment and collaboration between national registers: the Nordic example JF RMD Open JO RMD Open FD EULAR SP rmdopen-2018-000655corr1 DO 10.1136/rmdopen-2018-000655corr1 VO 4 IS 1 YR 2018 UL http://rmdopen.bmj.com/content/4/1/rmdopen-2018-000655corr1.abstract AB