[Regional external quality control of the analysis of urinary calculi]

Within one year's period a model for external quality control of urolithiasis was tested. This model includes specifications concerning precision as well as accuracy derived from diagnostic and therapeutic considerations. The quality indices obtained for precision QI-P and accuracy QI-R confirm that all analytical centres of urolithiasis in the GDR are to be found under the fixed specifications, partially to a considerable extent. Thus all participants indirectly demonstrated that the state of adjustment of instrumentation and thereby the reference factors remain stable for at least one year. The system being continued the specifications of precision (ST 0%) and accuracy (D0) might even be fixed more exactly from an analytical point of view.