Report on a joint European quality control survey for neonatal thyrotropin determinations (1986)

This paper presents the results of a joint European external quality control survey for thyrotropin determinations in blood dried on filter paper, carried out in 1986 in cooperation with several national quality control organizations. For the evaluation, 124 participants presented their individual diagnostic classifications in addition to their analytical results. Although, in relation to earlier studies of this kind, there was a significant improvement in interlaboratory precision the results still showed variance which depended on the analytical method and, possibly on the country in which it was performed. Regional differences were also evident in the diagnostic classifications.