The 14th quality control survey for radioisotope in vitro tests in Japan, 1992

This report presents the results of the 14th quality control nationwide survey. Of 490 facilities performing RI in vitro tests as of December 1992, 261 (53.3%) participated in the present 1992 survey. Free testosterone and renin were added to the following conventional 37 test items: adrenocorticotropic hormone (ACTH), growth hormone (GH), somatomedin C, follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin, thyroid stimulating hormone (TSH), triiodothyronine (T3), free T3, thyroxine (T4), free T4, T3 uptake, thyroglobulin, T3 binding globulin (TBG), parathyroid hormone (PTH), calcitonin, insulin, C-peptide, glucagon, gastrin, testosterone, estradiol, progesterone, 17α-hydroxyprogesterone, aldosterone, cortisol, immunoglobulin E (IgE), digoxin, α-fetoprotein, carcinoembryonic antigen (CEA), tissue polypeptide antigen (TPA), CA125, CA19-9, CA15-3, prostatic acid phosphatase (PAP), β2-microglobulin, and ferritin. Measurement data for each kit were analyzed by a mean value of measurements, standard deviation, and coefficient of variation (CV). Both 'within kit variation' between facilities and 'between kit variation' showed a CV of 20% or less for GH, somatomedin C, TSH, T3, T4, T3 uptake, TBG, cortisol, IgE, CA125, PAP, and β2-microglobulin, revealing satisfactory results. There was a great 'within kit variation' between facilities in ACTH, free T4, and calcitonin; and there was a great 'between kit variation' in ACTH, LH, free T4, thyroglobulin, PTH, calcitonin, and α-fetoprotein. (N.K.)