Vitamin D Deficiency in Children with a Chronic Illness–Seasonal and Age-Related Variations in Serum 25-hydroxy Vitamin D Concentrations

• Elisa Holmlund-Suila ,

  Contributed equally to this work with: Elisa Holmlund-Suila, Panu Koskivirta

  Affiliation Children’s Hospital, Helsinki University Central Hospital and University of Helsinki, Helsinki, Finland

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• Panu Koskivirta ,

  Contributed equally to this work with: Elisa Holmlund-Suila, Panu Koskivirta

  Affiliation Children’s Hospital, Helsinki University Central Hospital and University of Helsinki, Helsinki, Finland

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• Tuula Metso,

  Affiliation Skin and Allergy Hospital, Division of Allergy, Helsinki University Central Hospital, Helsinki, Finland

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• Sture Andersson,

  Affiliation Children’s Hospital, Helsinki University Central Hospital and University of Helsinki, Helsinki, Finland

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• Outi Mäkitie,

  Affiliations Children’s Hospital, Helsinki University Central Hospital and University of Helsinki, Helsinki, Finland, Folkhälsan Research Center, Helsinki, Finland

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• Heli T. Viljakainen

  * E-mail: heli.viljakainen@helsinki.fi

  Affiliations Children’s Hospital, Helsinki University Central Hospital and University of Helsinki, Helsinki, Finland, Musculoskeletal Research Unit, University of Bristol, Bristol, United Kingdom

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