Received: 9 July 2018
Accepted: 29 October 2018
First Online: 13 November 2018
Ethics approval and consent to participate
: This human study was approved by The University of Pennsylvania - approval: 824466. All adult participants provided written informed consent to participate in this study.
: This submission does not contain any individual data.
: One author (JB) is an associate editor for BMC Musculoskeletal Disorders. None of the other authors have any competing interests.
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