Physical activity level at work and risk of chronic low back pain: A follow-up in the Nord-Trøndelag Health Study

• Ingrid Heuch ,

  * E-mail: ingrid.heuch@ous-hf.no

  Affiliation Department of Neurology and FORMI, Oslo University Hospital, Oslo, Norway

  http://orcid.org/0000-0003-1202-730X

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• Ivar Heuch,

  Affiliation Department of Mathematics, University of Bergen, Bergen, Norway

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• Knut Hagen,

  Affiliations Department of Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway, Norwegian National Headache Centre, Department of Neurology, St. Olavs Hospital, Trondheim, Norway

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• John-Anker Zwart

  Affiliations Department of Neurology and FORMI, Oslo University Hospital, Oslo, Norway, Faculty of Medicine, University of Oslo, Oslo, Norway

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