Defining Use and Misuse of BIoMarkers Dosage and Trends in Observed Concentration Over Time: a BIg Data Analysis

The rUBIDIuM study is a retrospective analysis that included all tests (but not including DNA analysis or HIV tests) performed in a large subset of laboratories located in the French Brittany from February 2010 the 17th to August 2015 the 30th. The area of study covers most of the Ille-et-Vilaine and a part of the Côtes d'Armor department in Brittany. The respective surface of these departments is 6775 and 6878 km2. All labs belong to the Biorance Laboratory group (consortium of 33 labs, Biorance Laboratoires Réunis) and are equipped with Roche Diagnostics instruments (Elecsys2010® analyzer, Roche diagnostics, Meylan, France).

The main objectives are to study physicians' use and eventually misuse of biomarkers dosage and the characteristics of this broad population based on some biomarkers concentrations.

For all adult patients >20y that came to a participating lab during the study period, the investigators collected the following information: demographics data, data about the prescription (date of order, list of analysis recommended, the date of blood collection and analysis), about the prescribers and the results of the analyses. After a de-identifying process, data were aggregated.

the initial analyses will 1) examine the biological tests (number, types...) ordered in a large cohort of patients, in the total population and the subgroups based on gender, age, time period, kind of lab and physicians' specialty, 2) examine the results/concentration of the analyses: blood chemistry, creatinin concentration, cardiac enzymes, natriuretic peptides, INR, lipid profile, hemogram...