Biomedical subjects

J V García-Lario

Publications and source records attributed to J V García-Lario.

3 recordsLinked to original sources

PubMed2004

The reference change value: a proposal to interpret laboratory reports in serial testing based on biological variation.

BACKGROUND: A proposal to calculate and use the reference change value (RCV) as an objective guide for interpreting the numerical results obtained in clinical laboratory serial testing is introduced in this study. METHODS: A database showing the results of a compilation of 191 publications on biological variation and including information on a number of analytes provided the standardized criterion based on biology for calculating the RCVs. RESULTS: For each of the 261 analytes included in the study, the RCV was determined using Harris's formula, replacing analytical imprecision with the desirable specification of analytical quality based on half the within-subject biological variation at 95% probability levels. The result is a guide for a common criterion to identify clinically significant changes in serial results. CONCLUSIONS: The RCV concept is an approach that can be offered by laboratories to assess changes in serial results. The RCV data in this study are presented as a point of departure for a widely applicable objective guide to interpret changes in serial results.

Algorithms↗

PubMed2001

Multicentric reference values for some quantities measured with the Elecsys 2010 analyser.

Several clinical laboratories in different regions of Spain have shared the search for reference individuals and the production of reference values for quantities concerning thyrotropin, non-protein bound thyroxine, triiodothyronine, cobalamines and folates, using an Elecsys 2010 analyser. All the logistic work has been done in co-operation with the supplier of the analyser (Roche Diagnostics España, S.L., Barcelona). The reference limits produced in the virtual laboratory are in fact derived from the blend of reference values obtained by each laboratory. The multicentric reference limits were estimated according to the recommendations of the International Federation of Clinical Chemistry. The work done represents a model of co-operation between the in vitro diagnostic industry and clinical laboratories for the production of reference values.

Reference Standards↗

PubMed1999

Current databases on biological variation: pros, cons and progress.

A database with reliable information to derive definitive analytical quality specifications for a large number of clinical laboratory tests was prepared in this work. This was achieved by comparing and correlating descriptive data and relevant observations with the biological variation information, an approach that had not been used in the previous efforts of this type. The material compiled in the database was obtained from published articles referenced in BIOS, CURRENT CONTENTS, EMBASE and MEDLINE using "biological variation & laboratory medicine" as key words, as well as books and doctoral theses provided by their authors. The database covers 316 quantities and reviews 191 articles, fewer than 10 of which had to be rejected. The within- and between-subject coefficients of variation and the subsequent desirable quality specifications for precision, bias and total error for all the quantities accepted are presented. Sex-related stratification of results was justified for only four quantities and, in these cases, quality specifications were derived from the group with lower within-subject variation. For certain quantities, biological variation in pathological states was higher than in the healthy state. In these cases, quality specifications were derived only from the healthy population (most stringent). Several quantities (particularly hormones) have been treated in very few articles and the results found are highly discrepant. Therefore, professionals in laboratory medicine should be strongly encouraged to study the quantities for which results are discrepant, the 90 quantities described in only one paper and the numerous quantities that have not been the subject of study.

Clinical Laboratory Techniques↗