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Updated: Jun 10, 2026
Comparative Analysis of Human Growth Hormone in Serum Using SPRi, Nano-SPRi and ELISA Assays
Published on: January 7, 2016
Normal values of serum IGF-1 in adults: results from a Brazilian population
1Santa Casa de Belo Horizonte, Departamento de Neuroendocrinologia, Santa Casa de Belo Horizonte, MG, Brazil. pedrorosario@globo.com
Objective:
To determine the normal values of serum IGF-1 (Immulite 2000) in a Brazilian adult (21-70 years) population.
Subjects And Methods:
Healthy volunteers were divided into 10 groups according to age (5-year intervals), with 100 subjects (50 men and 50 women) per group. One-hundred participants were selected for repetition of the test after 12 weeks.
Results:
No difference in IGF-1 values was observed between men and women, but a progressive reduction of serum IGF-1 with age was seen. The reference values provided by the manufacturer of the assay, although discretely higher, were very close to the values found in this study. A second measurement of IGF-1 after 12 weeks revealed a variation < 20% in 99% of subjects.
Conclusions:
This study established the reference range for IGF-1 determined with the Immulite 2000 assay for a large number of healthy Brazilian adults stratified according to age, and suggests that variations > 20% in IGF-1 levels within an interval of 12 weeks cannot be attributed to interassay variability.
