## 3 Results and Discussion
### Guarantee of Transferability of Results  
To assess the transferability of results between different machines and positions, we perform the assessment of patient samples analyzed by the two machines. All are compared by Bland-Altman charts [31]. From the Bland-Altman charts (see Figures 6-12) one can see the lines of the confidence intervals among which it need to contain the zero value. The continuous red lines correspond to the values of the maximum analytical quality goals obtained from the error goals for the Spanish external quality control program of the analytical laboratories of the Fundacio Pel Control de Qualitat dells Laboratories Clinics (FPCQLC). In the charts, it also identifies the analysers and the analytical modules and the operative channels of each module. Figure 6: Comparison between modules for the TSH parameter in which it have compared the results obtained by the measurements performed in the two machines (Analyser C3 substituted by C2 in which the Module 2 is substituted by the module M1 and the channel X2 is substituted by the channel X1). Figure 7: Comparison between modules for the Vitamin B12 parameter in which we have compared the results obtained by the measurements performed in the two machines (Analyzer C3 substituted by C2 in which the Module 1 is substituted by the Module M2 and the Channel X1 is substituted by the Channel X1). Figure 8: Comparison between modules for the Folate parameter in which we have compared the results obtained by the measurements performed in the two machines (Analyzer C3 substituted by C2 in which the Module 3 is substituted by the Module M1 and the Channel X1 is substituted by the Channel X2). Figure 9: Comparison between modules for the Vitamin D parameter in which we have compared the results obtained by the measurements performed in the two machines (Analyzer C3 substituted by C2 in which the Module 2 is substituted by the Module M2 and the Channel X1 is substituted by the Channel X1). Figure 11: Comparison between modules for the parameter Free T4 in which we have compared the results obtained by the measurements performed in the two machines (Analyzer C3 substituted by C2 in which the Module 2 is substituted by the Module M3 and the Channel X1 is substituted by the Channel X1). Figure 10: Comparison between modules for the Ferritin parameter in which we have compared the results obtained by the measurements performed in the two machines (Analyzer C3 substituted by C2 in which the Module 3 is substituted by the Module M3 and the Channel X2 is substituted by the Channel X2). We did not perform any comparatives from techniques that do not require machine transfer. In Figure 6 one can observe parameter TSH for comparing the value obtained for the same serums of different samples in both instrumental arrangements analyzed. One can see the minimal difference between the results of analyzers. In Figure 7 one can observe parameter Vitamin B 12 for comparing the value obtained for the same serums of different samples in both instrumental arrangements analyzed. One can see the minimal difference between the results of analyzers. In Figure 8 one can observe parameter Folate for comparing the value obtained for the same serums of different samples in both instrumental arrangements analyzed. One can see the deviation into the interval of confidence between the results of analyzers. In Figure 9 one can observe parameter Vitamin D for comparing the value obtained for the same serums of different samples in both instrumental arrangements analyzed. One can see the minimal difference between the results of analyzers. In Figure 10 it can observe parameter Ferritin for comparing the value obtained for the same serums of different samples in both instrumental arrangements analyzed. It can see the minimal difference between the results of analyzers with a less tendency to target and confidence interval.