## 4 Discussion
\begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline  & & & **HIV** & & \multicolumn{3}{c}{**COVID-COVIDGG (*)**} & \multicolumn{3}{c}{**All Serology Tests**} \\ \hline  & & **Pre-TLA** & **Post-TLA** & \begin{tabular}{c} **Improvement** \\ **Ratio** \\ \end{tabular} & **Pre-TLA** & **Post-TLA** & \begin{tabular}{c} **Improvement** \\ **Ratio** \\ \end{tabular} & **Pre-TLA** & **Post-TLA** \\ \hline \multirow{5}{*}{\begin{tabular}{c} Equipment per test \\ (EUR/test) \\ \end{tabular} } & Equipment per test & & 0.65 & & **1.66** & 0.0\% & & \\  & \multirow{2}{*}{\begin{tabular}{c} Reagents per test \\ (EUR/test) \\ \end{tabular} } & Reagents per test & & 1.23 & & **6.36** & 0.0\% & & \\  & \multirow{2}{*}{\begin{tabular}{c} Direct labour cost \\ per test (EUR/test) \\ \end{tabular} } & Direct labour cost & & 1.78 & 10.9\% & 1.92 & 1.78 & 7.1\% & \\  & \multirow{2}{*}{\begin{tabular}{c} Average cost per \\ test (EUR/test) \\ \end{tabular} } & Average cost per & & 4.1 & 3.67 & 10.6\% & 9.94 & 9.81 & 1.4\% & \\  & \multirow{2}{*}{\begin{tabular}{c} Test volume 2022 \\ (units) \\ \end{tabular} } & Test volume & & 29,216 & & & 18,273 & & \\  & \multirow{2}{*}{\begin{tabular}{c} Cost savings/year \\ (EUR) \\ \end{tabular} } & Cost savings/year & & & 12,706.84 & & & 2505.39 & & \\  & \multirow{2}{*}{\begin{tabular}{c} Average test \\ number/day (units) \\ \end{tabular} } & Average test & 109 & 118 & & 311 & 74 & 855 & 851 \\  & \multirow{2}{*}{\begin{tabular}{c} Full time equivalent \\ (FTE) \\ \end{tabular} } & Full time equivalent & 0.70 & 0.42 & 40.0\% & 0.44 & 0.26 & 40.0\% & 5 & 3 \\ \cline{2-8}  & Processing (FTE) & & & & & & 3 & 2 \\ \cline{2-8}  & Validation (FTE) & & & & & & 2 & 1 \\ \cline{2-8}  & \multirow{2}{*}{\begin{tabular}{c} Productivity \\ (tests/FTE) \\ \end{tabular} } & Procesing & & & & & & 171 & 284 \\  & \multirow{2}{*}{\begin{tabular}{c} Validation \\ (tests/FTE) \\ \end{tabular} } & Processing & & & & & 285 & 426 \\  & \multirow{2}{*}{\
\begin{tabular}{c} Validation \\ (tests/FTE) \\ \end{tabular} } & Validation & & & & & 428 & 851 \\  & \multirow{2}{*}{
\begin{tabular}{c} * The cost considers one sample with two different determinations, one for each serology analysis: COVT and COVIDGG. (**) No data available. (***) Serology tests: AVIH, HBS, VHC, LUES, HBCC, AHBS, COVT, TXG, RUBG, CMVG, HAVG, CMVM, HAVM, HTLV, TXM, CHAGAS, COVIDG, EBM, EBNAG, VZG, PARG, SARG, PARVOC, HSG, EBG, BORG, PARVOM, BORM. & & & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Comparison of cost and process KPIs per serology test in pre-TLA and post-TLA scenarios. with substantially different workflow processes. However, our findings and the adoption of Lean principles can still offer valuable insights to other laboratories, albeit with some contextual adaptation. Quality in terms of patient satisfaction could have been another research variable resulting from our process improvement initiatives. Therefore, it is reasonable to infer that reduced waiting times and improved Turnaround Times (TATs) would likely lead to increased patient satisfaction. The advantages were expanded to encompass other sections of the laboratory, including the pre-analytical area, where certain specimens still undergo manual processing but with a noticeably reduced workload. Notably, the automation has led to a remarkable reduction in laboratory waste. Nevertheless, there are still potential improvements under analysis that will enhance the current situation in the near future. They are related to the sample input and output processes of the serology-automated line, such as creating a pull flow between the sample incoming area and the pre-analytical equipment or eliminating the finished sample re-racking for sample archiving. In addition, pre-analytical equipment idle times could be also reduced improving the line schedule and levelling.