Tradition & Heritage Timeline Artifacts  
Advances in Medicine
Dr. Leonard Kurland
Dr. Leonard Kurland -- Rochester Epidemiology Project

In the early 1900s, the Mayo brothers asked Dr. Henry Plummer to organize files so that physicians could consult one dossier for a patient's complete medical history. The dossiers and patients were linked by a Mayo identification number to protect patient confidentiality, a system still used today.

In order to use the dossiers for medical research, Dr. Plummer and his assistant, Mabel Root, expanded the system in 1910 by recording patient information and the patient's identification number on 5-inch-by-8-inch cards that could contain hundreds of entries for a disease diagnosis or surgical procedure.

As the years passed, the system was upgraded. In 1935, Dr. Joseph Berkson introduced a more comprehensive indexing system so that conditions could be more easily identified for study. But it was Dr. Leonard Kurland, a consultant in epidemiology, who envisioned expanding the medical records system beyond Mayo Clinic to generate studies based on the population of Olmsted County. In 1966, Dr. Kurland obtained National Institutes of Health (NIH) funding to link records of all the county's health care providers. With this, the Rochester Epidemiology Project (REP) was born. Records were computerized in 1975.

The REP is a system for accessing medical records of virtually the entire population of Olmsted County since the records were kept. It is so wide-ranging in its inclusion of all county residents -- encompassing all ages, races, income levels and degrees of illness -- that Mayo studies resulting from the use of this system are considered among the best medical research in the world. Studies determining the incidence, long-term trends and outcomes of virtually every major disease have been published and extrapolated to portray the U.S. population at large. More than 1,500 studies have drawn on its millions of files, yielding the REP an international reputation.

Circular Nursing Units Telemedicine at Mayo

Find Mayo Clinic on


Terms of Use and Information Applicable to this Site
Copyright ©2001-2014 Mayo Foundation for Medical Education and Research. All Rights Reserved.