Christensen T, Riis AH, Hatch EE, Wise LA, Nielsen MG, Rothman KJ, Toft Sorensen H, Mikkelsen EM. Costs and efficiency of online and offline recruitment methods: a web-based cohort study. J Med Internet Res. 2017 Mar 1;19(3):e58. doi: 10.2196/jmir.6716
Primatesta P, Plana Hortoneda E, Rothenbacher D. Gout treatment and comorbidities: a retrospective cohort study in a large US managed care population. BMC Musculoskelet Disord. 2011 May 20;12:103. doi: 10.1186/1471-2474-12-103
Petit A, Castillo M, Gaspa A, Colomer D, Garcia de Albeniz X, Moreno C, Camos M, Mellado B, Mallofre C. Expression and mutational analyses of KIT and PDGFR-alpha in sarcomatoid renal cell carcinoma. Histopathology. 2009 Aug;55(2):230-2. doi: 10.1111/j.1365-2559.2009.03342.x