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The first step to complete in a method validation of a biological analysis is the study of precision intra-assay. In the absence or insufficient quantity of control material, this study may be difficult to perform. This article proposes a methodology for preparing its own control samples for the radioimmunological assay of the amino-terminal peptide of procollagene type III (PIIIP). This methodology is easy to carry out, cost-effective and can be applied to analyses other than PIIIP. Furthermore, it allows the execution of control samples which have similar concentrations of analytes to those described in the precision studies of the datasheets provided by the manufacturers.

The study of the crystalluria is the search and the identification for crystals in urines. This multi-parametric study brings a precious help in the diagnosis and/or the follow-up of acquired or congenital lithiasis. The lack of the internal urinary quality control (IQC) makes the accreditation of this analysis, according to the NF EN ISO 15189 standard, particularly delicate. After a presentation of the three steps (pre-analytical, analytical and post-analytical) performed in the laboratory, the authors present some insights in order to mitigate the lack of the urinary IQC. These insights, particularly concern by the "misappropriation" of IQC, the elaboration of an "in house" IQC as well as by the evaluation of the external evaluation of the quality. Thanks to the implementation of these tools, it becomes easier to prove that the laboratory of medical biology masters the qualification, the authorization and the continuous preservation of the skills of the operators performing the study of the crystalluria.

In the perspective of a future request of accreditation according to the NF EN 15189 standard of the sector of prenatal diagnosis of the trisomy 21 foetal, we compared the results obtained for AFP, hCG, free hCG, PAPP-A and for the risks, according to 2 types of blood collection tubes: sterile tube and sterile tube with inert gel barrier. For 107 patients, the study of the Passing-Bablok regressions between the results from the 2 kinds of tubes, showed perfect correlations for measured biochemical markers (AFP, hCG, free hCG and PAPP-A) as well as for the estimated risks. A patient who presented a higher risk of foetal trisomy 21 (risk at 1/244) for the serum from the sterile tube was not in the high-risk area for the serum from the sterile tube with inert gel barrier (risk at 1/295). The fact that these 2 values of risk are very close to the threshold fixed to 1/250 can probably explain the observed conflict. Working on sterile tube, this study confirms that the requests of prenatal diagnosis of the trisomy 21 foetal taken from tube with inert gel barrier which we receive of outer laboratories.

In addition to NF EN ISO 15189, the second version of "GBEA AMP", published in the official journal of the French Republic, had set for "AMP" exams, the actions to be implemented in order to achieve an efficient quality management system. As part of continuous improvement of quality, and besides our external and internal quality systems, we have been developping indicators that will allow an early detection of potential drifts within operators performing sperm morphology testing. We have extracted nearly 1900 sperm morphology tests from our database. These tests were performed by three operators. The analysis of the data collected has shown a cross correlation between the percentages of typical forms, malformative acrosomes and "MAI". We have been using these correlations as quality indicators in our laboratory in order to highlight any potential drift in reading sperm morphology tests.