1. History of the Rochester Epidemiology Project: Half a Century of Medical Records Linkage in a US Population 
Walter A. Rocca, MD, MPH, Barbara P. Yawn, MD, MSc, Jennifer L. St. Sauver, PhD, MPH, Brandon R. Grossardt, MS, L. Joseph Melton, MD, MPH 
Mayo Clinic Proceedings 
Volume 87, Issue 12, Pages (December 2012)
DOI: /j.mayocp
Copyright © 2012 Mayo Foundation for Medical Education and Research Terms and Conditions

2. FIGURE 1
A, The father, W. W. Mayo ( , center), and the 2 Mayo brothers, W. J. Mayo ( , right) and C. H. Mayo ( , left). B, Leather-bound ledgers used before C, H. S. Plummer ( ). D, The new medical record introduced by Dr Plummer in 1907 to assemble forms for each patient into a dossier (paper file).
Photographs courtesy of the Mayo Historical Unit, Mayo Clinic, Rochester, Minnesota.
Mayo Clinic Proceedings  , DOI: ( /j.mayocp )
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3. FIGURE 2
A, Mabel Root ( ), secretary to Dr Plummer. B, Index card listing patients seen at Mayo Clinic for hypothyroidism (organ = thyroid; disease = hypothyroidism). C, J. Berkson ( ). D, A Hollerith punch card used for mechanical data processing.
Photographs courtesy of the Mayo Historical Unit, Mayo Clinic, Rochester, Minnesota.
Mayo Clinic Proceedings  , DOI: ( /j.mayocp )
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4. FIGURE 3
A, L. T. Kurland ( ), founder of the Rochester Epidemiology Project. B, L. J. Melton III (1944-). C, Current logo of the Rochester Epidemiology Project.
Photographs courtesy of the Mayo Historical Unit, Mayo Clinic, Rochester, Minnesota.
Mayo Clinic Proceedings  , DOI: ( /j.mayocp )
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5. FIGURE 4
Scheme of the steps involved in linking medical records, indexing diagnoses and other data, and retrieving medical records for a research study.
Mayo Clinic Proceedings  , DOI: ( /j.mayocp )
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