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Permanent URI for this collectionhttps://hdl.handle.net/11443/932

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Subject: search.filters.subject.Six Sigma

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Now showing 1 - 4 of 4
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    Wrong Sigma metric causes chaos
    (WALTER DE GRUYTER GMBH, 2022-01-01) Coskun, Abdurrahman
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    Six Sigma revisited: We need evidence to include a 1.5 SD shift in the extraanalytical phase of the total testing process
    (CROATIAN SOC MEDICAL BIOCHEMISTRY \& LABORATORY MEDICINE, 2020-01-01) Coskun, Abdurrahman; Ialongo, Cristiano
    The Six Sigma methodology has been widely implemented in industry, healthcare, and laboratory medicine since the mid-1980s. The performance of a process is evaluated by the sigma metric (SM), and 6 sigma represents world class performance, which implies that only 3.4 or less defects (or errors) per million opportunities (DPMO) are expected to occur. However, statistically, 6 sigma corresponds to 0.002 DPMO rather than 3.4 DPMO. The reason for this difference is the introduction of a 1.5 standard deviation (SD) shift to account for the random variation of the process around its target. In contrast, a 1.5 SD shift should be taken into account for normally distributed data, such as the analytical phase of the total testing process
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    Measurement uncertainty in laboratory medicine: the bridge between medical and industrial metrology
    (WALTER DE GRUYTER GMBH, 2019-01-01) Coskun, Abdurrahman; Inal, Berrin Bercik; Serdar, Muhittin
    Uncertainty is an inseparable part of all types of measurements, that is, in metrology a measurement without uncertainty is not possible. Calculation of uncertainty increases the awareness of the certainty of measurement results. Reporting measurement uncertainty is mandatory in almost all industrial sectors but not in laboratory medicine. Test results without analytical uncertainty increases the diagnostic uncertainty, causing errors that could seriously affect patients health. To improve diagnostic certainty, we should calculate and upon request report measurement uncertainty to laboratory users (ISO 15189). In this mini-review, we summarized the theoretical perspective of uncertainty concept, its relation to Six Sigma and finally compared it with Total Error Method.
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    Sigma metric revisited: True known mistakes
    (CROATIAN SOC MEDICAL BIOCHEMISTRY \& LABORATORY MEDICINE, 2019-01-01) Coskun, Abdurrahman; Serteser, Mustafa; Unsal, Ibrahim
    Six Sigma methodology has been used successfully in industry since the mid-1980s. Unfortunately, the same success has not been achieved in laboratory medicine. In this case, although the multidisciplinary structure of laboratory medicine is an important factor, the concept and statistical principles of Six Sigma have not been transferred correctly from industry to laboratory medicine. Furthermore, the performance of instruments and methods used in laboratory medicine is calculated by a modified equation that produces a value lower than the actual level. This causes unnecessary, increasing pressure on manufacturers in the market. We concluded that accurate implementation of the sigma metric in laboratory medicine is essential to protect both manufacturers by calculating the actual performance level of instruments, and patients by calculating the actual error rates.