Authors’ contributions
AR, designed the study, funded the PhD project, performed statistical analyses, and contributed in writing the manuscript. MK contributed to data collection, strain analysis, statistical analysis, and writing of the manuscript. HAC worked on artifact analysis and strain analysis for the inter-observer-variability. AVK collected data in Arkhangelsk and participated in the manuscript writing. SM and ARy were responsible for funding acquisition and data collection in Novosibirsk, in addition to writing the manuscript. SQ contributed by automated data-extraction and analysis and writing of the manuscript. HS arranged funding and execution of the Tromsø7 study and also contributed to writing the manuscript.