Ontology highlight
ABSTRACT: Context
Measurement of IGF-I is essential for diagnosis and management of patients with disorders affecting the somatotropic axis. However, even when IGF-I kit manufacturers follow recent consensus guidelines, different kits can give very different results for a given sample.Objectives
We sought to establish normative data for six IGF-I assay kits based on a large random sample of the French general adult population.Subjects and methods
In a cross-sectional multicenter cohort study, we measured IGF-I in 911 healthy adults (18-90 years) with six immunoassays (iSYS, LIAISON XL, IMMULITE, IGFI RIACT, Mediagnost ELISA, and Mediagnost RIA). Pairwise concordance between assays was assessed with Bland-Altman plots for both IGF-1 raw data and standard deviation scores (SDS), as well as with the percentage of observed agreement and the weighted Kappa coefficient for categorized IGF-I SDS.Results
Normative data included the range of values (2.5-97.5 percentiles) given by the six IGF-I assays according to age group and sex. A formula for SDS calculation is provided. Although the lower limits of the reference intervals of the six assays were similar, the upper limits varied markedly. Pairwise concordances were moderate to good (0.38-0.70).Conclusion
Despite being obtained in the same healthy population, the reference intervals of the six commercial IGF-1 assay kits showed noteworthy differences. Agreement between methods was moderate to good.
SUBMITTER: Chanson P
PROVIDER: S-EPMC5054194 | biostudies-literature | 2016 Sep
REPOSITORIES: biostudies-literature
Chanson Philippe P Arnoux Armelle A Mavromati Maria M Brailly-Tabard Sylvie S Massart Catherine C Young Jacques J Piketty Marie-Liesse ML Souberbielle Jean-Claude JC
The Journal of clinical endocrinology and metabolism 20160511 9
<h4>Context</h4>Measurement of IGF-I is essential for diagnosis and management of patients with disorders affecting the somatotropic axis. However, even when IGF-I kit manufacturers follow recent consensus guidelines, different kits can give very different results for a given sample.<h4>Objectives</h4>We sought to establish normative data for six IGF-I assay kits based on a large random sample of the French general adult population.<h4>Subjects and methods</h4>In a cross-sectional multicenter co ...[more]