Randsborg, Per-Henrik, Einar A Sivertsen, Inge Skråmm, J rat Šaltyt Benth, and Pål Gulbrandsen. 2010. “The Need for Better Analysis of Observational Studies in Orthopedics”. Acta Orthopaedica 81 (3):377-81. https://doi.org/10.3109/17453674.2010.487243.