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Volume 7, Issue 5 (Suppl) Epidemiology (Sunnyvale), an open access journal
ISSN: 2161-1165 Epidemiology 2017
October 23-25, 2017
Page 40
conferenceseries.com
EPIDEMIOLOGY & PUBLIC HEALTH
October 23-25, 2017 | Paris, France
6th International Conference on
Henry Völzke, Epidemiology (Sunnyvale) 2017, 7:5(Suppl)
DOI: 10.4172/2161-1165-C1-016
REFERENCE VALUES AND THERAPEUTIC CUT-OFFS - EPIDEMIOLOGISTS CAN HELP
REDUCE CONFUSION OF CLINICIANS
It is a common error in thinking of clinicians to hope that a reference value could help finding the right treatment decision. In
general, reference values are nothing else than distribution markers of a clinical test among a healthy reference population,
as analysed from cross-sectional studies. The value distribution is highly dependent on factors affecting the population and the
selection of the reference population. The question that can be answered by analysing reference intervals is only the question on
what is high or low or, more in general, what is usual in a given population. Values outside a reference range indicate that there
is a high probability that the patient is not “healthy”, which may require further diagnostic work-up. Reference values, however,
are not sufficient to decide upon treatment initiation. Valid answers to the question on whether high or low values should be
treated or not require 1) clinical information on symptoms, co-morbidities and other diagnostic findings and/or 2) longitudinal
studies on outcomes related on a given baseline level. Current epidemiology increasingly comprises large-scale population
studies with comprehensive information from medical examinations. These studies offer optimal conditions for reference
and cut-off value analyses by 1) results generalizable to the population under investigation, 2) validity in selecting reference
populations by not only considering clinical diseases but also subclinical disorders to define health, and 3) high precision by
large study populations. Comprehensive statistical methods such as quintile regression allows establishing individual reference
values by considering physiological factors influencing test values including, for example, sex, age, body weight and height.
Biography
Henry Volzke is Professor for Clinical-Epidemiological Research with basic training as Certified Internist. He has been involved in research projects funded by the Euro-
pean Union, the German Research Foundation and numerous other public and private funding bodies and is member of several large national and international research
consortia. His broad research interests cover common population-relevant diseases including thyroid and other endocrine disorders, cardiovascular, metabolic and gas-
trointestinal diseases. In PubMed, he is listed with more than 620 publications in international peer-reviewed journals. He is PI of the Studies of Health in Pomerania and
the Northeast German part of the German National Cohort as well as Co-PI of the GANI_MED project and the Greifswald site of the German Centre for Cardiovascular
Research. He coordinates the H2020 funded EUthyroid Consortium. He is past President of the German Society for Epidemiology (DGEpi) e.V and the German Repre-
sentative in the Iodine Global Network.
Henry Völzke
University Medicine Greifswald, Germany