TY - JOUR 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 DO - 10.1136/rmdopen-2018-000655corr1 VL - 4 IS - 1 SP - rmdopen-2018-000655corr1 A2 - , Y1 - 2018/05/01 UR - http://rmdopen.bmj.com/content/4/1/rmdopen-2018-000655corr1.abstract N2 - Chatzidionysiou K, Hetland ML, Frisell T, et al. Opportunities and challenges for real-world studies on chronic inflammatory joint diseases … ER -