[en] Because the long incubation time (4 days for the first incubation and 1 day for the second) needed for conventional HTSH radioimmunoassay kits is thought to reduce their clinical applicability, the authors attempted to develop. Bound percent of the zero samples decreased exponentially according to the increase in first incubation volume (0.2-0.7 ml). This decrease was greater in a low standard HTSH concentration than in a high one. Rapid processing procedure of HTSH radioimmunoassay kits should be as follows: (1) First incubation volume: should be 0.4 ml. (2) First incubation temperature: could be any point between 20 and 30⁰C for 24+-4 hours. (3) Second incubation temperature and period after addition of second antibody could be chosen from any one of the following; (a) 25⁰C for 5+-2 hours (two days method when combined with first incubation at 25⁰C for 20 hours), (b) 4⁰C for 24 hours (three days method). (4) Centrifuge at 3000 rpm for 30 minutes immediately after addition of 0.5 ml of phosphate buffer. Both of the above two rapid processing procedures revealed satisfactory reproducibility and recovery rates. (Evans, J.)