Author Contributions: Ms Korhonen had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Study concept and design: Korhonen, Niemi, Parkkari, Kannus.
Acquisition of data: Korhonen, Niemi, Kannus.
Analysis and interpretation of data: Korhonen, Niemi, Parkkari, Sievänen, Kannus.
Drafting of the manuscript: Korhonen, Niemi, Parkkari, Kannus.
Critical revision of the manuscript for important intellectual content: Korhonen, Niemi, Parkkari, Sievänen, Kannus.
Statistical analysis: Korhonen, Niemi.
Obtained funding: Korhonen, Kannus.
Administrative, technical, or material support: Korhonen, Niemi, Parkkari, Sievänen, Kannus.
Study supervision: Parkkari, Kannus.
Conflict of Interest Disclosures: The authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Dr Sievänen reported receiving an institutional research grant from the Finnish Ministry for Culture and Education Research and a development grant from the Finnish Funding Agency for Technology and Innovation; and receiving dividends from stock in Nokia Corporation. No other disclosures were reported.
Funding/Support: This study was funded by comparative research funding from the Pirkanmaa Hospital District (Tampere, Finland) and a grant from the Finnish Medical Foundation (awarded to Ms Korhonen).
Role of the Sponsor: The funding organizations had no role in the design and conduct of the study; in the collection, analysis, and interpretation of the data; or in the preparation, review, or approval of the manuscript.