aMedical Research Unit, Spine Center of Southern Denmark, University Hospital of Southern Denmark, Middelfart

bDepartment of Regional Health Research, University of Southern, Odense, Denmark

dDepartment of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense

cResearch Unit of General Practice, Department of Public Health, University of Southern Denmark, Odense, Denmark

The device(s)/drug(s) that is/are the subject of this manuscript is/are exempt from FDA or corresponding national regulations. The device subject of this manuscript is a European conformity-marked accelerometer that is developed to be worn on the body to measure physical behavior and is not a medical device.

The study was presented to the regional ethics committee in 2018, which found that the protocol fell outside the definition of a notifiable health research project in Section 2, no. 1 of the Danish Act on Research Ethics Review of Health Research Projects (committee reference 20182000-128, documentation available upon request).

This study was supported by Beckett-Foundation, Tømmerhandler Johannes Fogs Foundation, Lillebaelt Hospital, The Region of Southern Denmark, and the Spine Center of Southern Denmark.

The authors report no conflicts of interest.

Address correspondence and reprint requests to Malin E.a.K. Gustafsson, MD, Middelfart Sygehus, Østre Hougvej 55, Middelfart 5500, Denmark; E-mail: [email protected]

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