Molecular Pathology
Maryam Sotoudeh Anvari; Atoosa Gharib; Maryam Abolhasani; Aileen Azari-Yaam; Farzaneh Hossieni Gharalari; Moeinadin Safavi; Ali Zare-Mirzaie; Mohammad Vasei
Abstract
Molecular assays for detection of nucleic acids in biologic specimens are valuable diagnostic tools supporting clinical diagnoses and therapeutic decisions. Pre-analytical errors, which occur before or during processing of nucleic acid extraction, contribute a significant role in common errors which ...
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Molecular assays for detection of nucleic acids in biologic specimens are valuable diagnostic tools supporting clinical diagnoses and therapeutic decisions. Pre-analytical errors, which occur before or during processing of nucleic acid extraction, contribute a significant role in common errors which take place in molecular laboratories. Certain practices in specimen collection, transportation, and storage can affect the integrity of nucleic acids before analysis. Applying best practices in these steps, helps to minimize those errors and leads to better decisions in patient diagnosis and treatment. Widely acceptable recommendations, which are for optimal molecular assays associated with pre-analytic variables, are limited. In this article, we have reviewed most of the important issues in sample handling from bed to bench before starting molecular tests, which can be used in diagnostic as well as research laboratories. We have addressed the most important pre-analytical points in performing molecular analysis in fixed and unfixed solid tissues, whole blood, serum, plasma, as well as most of the body fluids including urine, fecal and bronchial samples, as well as prenatal diagnosis samples.
Aileen Azari Yam; Peyman Mohammadi Torbati
Volume 6, Issue 1 , January 2011, , Pages 13-19
Abstract
Background and Objective: The reliability and validity of monitors for self-monitoring of blood glucose are debated. We evaluated the analytical performance of Accu-check Active (Boehringer Mannheim, Roche) which is one of the most commonly used monitors in Iran.
Material and Methods: We compared ...
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Background and Objective: The reliability and validity of monitors for self-monitoring of blood glucose are debated. We evaluated the analytical performance of Accu-check Active (Boehringer Mannheim, Roche) which is one of the most commonly used monitors in Iran.
Material and Methods: We compared the monitor readings with the reference values by percentage of values within certain intervals of the reference method, regression analysis, and difference plot. We used operational process specification charts to determine the probability that different QC rules would detect an analytical error. In addition, we assessed the quality on the sigma scale.
Results: This meter met International Organization for Standardization’s criteria but not the American Diabetes Association’s stringent criteria. The monitor produced precise readings throughout the concentration range and results correlated closely with the reference method. The measured total error was 6.39% (less than allowable total error of 10%). The method reached 6 sigma at glucose levels of 6.66 and 18.87 mmol/L and a sigma of 3 to 4 at glucose level of 2.49. Repeatability and intermediate precision were acceptable.
Discussion: We concluded that the overall performance of this instrument is reasonable but in hypoglycemic range, multiple control rules and control materials are required to assure the desired quality is achieved.
