Double-antibody immunoenzyme assay for human prostatic acid phosphatase.

Abstract
We compare the double-antibody radioimmunoassay (RIA) and immunoenzyme assay (IEA) for measuring the concentration of prostatic acid phosphatase in human serum. Experimental details and assay performance of the two methods are outlined. Mean values for 385 normal persons were 1.02 (SD 1.32) microgram/L by IEA, 2.69 (SD 1.8) microgram/L by RIA. Results of the two methods was highly correlated [r = 0.9813, y(RIA) = 0.35 x (IEA) + 0.42, p < 0.001]. If we choose x- + 2 SD as the normal range, 3-10% false positives were seen.