Valid measurements of total IGF concentrations in biological fluids: recommendations from the 3rd International Symposium on Insulin-like Growth Factors

At the 3rd International Symposium on Insulin-like Growth Factors, Sydney, Australia, 6–10 February 1994, a workshop was held focusing on problems commonly observed with measurements of total IGF concentrations. Although the interference of IGF binding proteins (IGFBPs) with measurements of total IGF concentrations has been acknowledged for a long time, the workshop demonstrated that there is still considerable confusion about validation procedures for IGF assays. With increasing use of IGF measurements in many branches of scientific research and clinical diagnosis, there has been a surprisingly large number of publications based on inadequately validated IGF measurements. A meeting of researchers who have been working with IGF assay problems decided to give the following recommendations for validation of IGF assays, aiming: to guide the increasing number of investigators who do or are planning to determine total IGF concentrations; to inform reviewers of manuscripts involving total IGF measurements that special attention