Is the quantification of IGFBP-3, a member of  the insulin-like growth factor-binding protein (IGFBP) family and encodes a protein with an IGFBP domain and a thyroglobulin type-I domain. Decreased  IIGFBP3 protein levels are used as a biomarker for prostate cancer progression. The trait is Experimental Factor Ontology term EFO_0004626 (IGFBP-3 measurement). Also known as: Insulin-Like Growth Factor Binding Protein 3 levels.