The role of the laboratory in healthcare – Supplier or a diagnostic partner?


Abstract: Diagnostic Pathways in Theory and Practice

It is generally accepted that the quality of test ordering impacts all subsequent steps in the laboratory diagnostic process. Nevertheless, significant over- and underuse of laboratory testing has always been a serious issue in medicine [1].

To overcome this problem, the German Association for Clinical Chemistry and Laboratory Medicine (DGKL) started an initiative In 2006, aiming to design and implement standardized diagnostic pathways [2]. In 2011, the task force published a widely recognized handbook, which is also available in English [3]. It includes more than 80 “algorithms”, which have been worked out jointly by laboratory and clinical experts and are based on published guidelines whenever possible.

Diagnostic pathways combine stepwise reflex testing with optimized processes and economic efficacy. The theoretical background of the approach is the Bayes theorem: By arranging the sequence of tests from high sensitivity to high specificity, the prevalence of the suspected disease is steadily increasing. This strategy minimizes false negative results in the beginning and false positive results at the end.

The computational basis of diagnostic pathways are expert rules (“if…then…else”), which can be visualized as decision trees. They represent “smart” test profiles, which are worked off just to a point, where the diagnostic decision can be made. The rules should be developed jointly by the clinicians and the laboratory and implemented in an electronic order entry system. Machine learning algorithms may be used to validate the decision limits and the efficiency of the test sequence.

Ideally, the requester would just mark the suspected diagnosis, and the laboratory would make sure that the answer is provided with high accuracy at low resource consumption. Thus, essential tests will never be missed, unnecessary requests will be avoided, and the role of the laboratory will change from being a supplier of numbers to becoming a diagnostic partner.

Welcome to Helsinki and International Congress on Quality in Laboratory Medicine to learn more. Dr. Hoffmann will give his presentation on Friday 9 February, 2018.

1. Salinas M, Lopez-Garrigos M, Rodriguez-Borja E et al. Laboratory test requesting: appropriateness and patient safety. De Gruyter, Berlin, 2016
2. Hoffmann G, Aufenanger J, Foedinger M, Cadamuro J, von Eckardstein A, Kaeslin-Meyer M, Hofmann W: Benefits and limitations of laboratory diagnostic pathways. Diagnosis 2014; 1: 269-76
3. Hofmann W, Aufenanger J, Hoffmann G. Laboratory diagnostic pathways. De Gruyter, Berlin, 2016


Georg Hoffmann on Labquality Days 2018Prof. Dr. med. Georg Hoffmann
Trillium GmbH, Germany

Georg Hoffmann was born in 1948. He received his M.D. from the Ludwig Maximilian University of Munich (LMU) in 1977 and accomplished degrees in clinical chemistry, medical informatics and laboratory medicine in 1982, 1989 and 1990, respectively. From 1995 to 1998, he was a guest professor at the University of Virginia in Charlottesville, VA, and in 1995 he became a Professor of Clinical Chemistry at the LMU.

He worked as a researcher at the Diabetes Research Institute Munich-Schwabing, as a department head of pathology in Munich-Bogenhausen and as a vice president of research and development for Boehringer Mannheim (now Roche).

In 1995, he founded the company Trillium GmbH, based in Grafrath, Germany with main business areas in strategic consulting, software development and public relations for industry, hospitals, and scientific organisations. Since 2014, the company has been a medical publishing house, which he manages together with his son Martin.

Prof. Hoffmann is a faculty member at the University of Munich, Germany, a publisher of the medicals magazines Trillium Diagnostik and Trillium Krebsmedizin (in German), chairman of a working group on Bioinformatics of the scientific association DGKL, as well as the author of two laboratory handbooks (in German and English), and more than 100 scientific publications.


International Congress on Quality in Laboratory Medicine 8-9 February, 2018 Helsinki, Finland

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