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Affiliations numbers 1 and 2 for the first, second and fourth authors are incorrect. The correct affiliation number 1 is: Institute of Preventive Medicine, Bispebjerg and Frederiksberg Hospital, Capital Region, Copenhagen, Denmark. The correct affiliation number 2 is: National Centre for Register-based Research, University of Aarhus, Aarhus, Denmark.
Competing Interests: No competing interests declared.
