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Published on: January 8, 2020
Testing bias in clinical databases: methodological considerations.
Karin J Velthove1, Hubert Gm Leufkens, Patrick C Souverein
1Faculty of Science, Division of Pharmacoepidemiology and Pharmacotherapy, Utrecht Institute of Pharmaceutical Sciences, Utrecht University, The Netherlands. H.G.M.Leufkens@uu.nl.
Laboratory testing bias for neutrophil counts is common in clinical practice. Requests for neutrophil counts are linked to underlying cardiovascular disease, highlighting the need to evaluate testing bias in database studies.
Area of Science:
- Clinical Medicine
- Hematology
- Epidemiology
Background:
- Laboratory testing is a critical component of clinical practice.
- Testing bias can influence the interpretation of laboratory results.
- This study investigates testing bias specifically for neutrophil counts.
Purpose of the Study:
- To evaluate testing bias for neutrophil counts in clinical practice.
- To compare requested versus non-requested neutrophil counts.
- To identify factors influencing testing bias.
Main Methods:
- Utilized data from the Utrecht Patient Oriented Database.
- Analyzed adult patients hospitalized in 2005 with multiple blood tests.
- Contrasted requested and non-requested neutrophil counts, considering diagnosis and glucocorticoid use.
Main Results:
- Analyzed 567 requested and 1,439 non-requested neutrophil counts.
- Found a significant difference in absolute neutrophil count at admission (7.4 vs. 8.3 x 10^9/L).
- Cardiovascular disease (83.2%) and glucocorticoid use (4.5%) explained the difference.
Conclusions:
- Neutrophil count requests in clinical databases are associated with underlying diseases, particularly cardiovascular disease.
- Testing bias is a crucial consideration in epidemiological studies using clinical database data.
- Emphasizes the importance of accounting for testing bias in research and clinical practice.
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