Some practical thoughts on restructuring the current guideline of the Federal Medical Council (Richtlinie der Bundesärztekammer [RiliBAK]) in Germany for quality control of clinical laboratory analyses based on results from external quality assessment surveys.

The present article presents a critical review of the current guidelines of the Federal Medical Council (Richtlinie der Bundesärztekammer--[RiliBAK]) in Germany, both for internal and external quality control. Examples have been chosen for analytes which present problems. These include thyrotropin (TSH) and human chorionic gonadotropin (hCG). Data are presented for the difference in analyte concentrations found between methods/kits and longitudinally for external quality assessment (EQA-) surveys for analytes using reference method values as target values. These include: calcium, aspartate aminotransferase (ASAT; GOT), aldosterone, cortisol, 17beta-oestradiol and total thyroxine (TT4). Furthermore, internal data from participating laboratories concerning laboratory internal precision and accuracy have been analysed to show the state of the art with regard to both parameters. Data analysis shows the need for a reintroduction of concentration-dependent assessment of performance (crossover system) for certain analytes, where clinically relevant concentrations are measured at the extremes of the calibration curve. The current guideline is at present being restructured and should include considerations made in this review of the state-of-the-art of clinical laboratory analysis.