## 2 Materials and Methods
### Testing Differences in Thermal Assessment Results  
To test whether the chairs differed in terms of the assessment of their thermal characteristics, a non-parametric Kruskal-Wallis test was performed, since the normal distribution of responses was not met as an assumption for conducting a one-way ANOVA test. The answers are divided into six groups, according to which chair they refer to. The analysis examined 15 different thermal indicators (T1-T15), likely representing various aspects of thermal and moisture performance that contribute to overall sitting comfort in office environments. The Kruskal-Wallis test did not indicate which of the tested chairs differed (paired test), but only the existence of differences between them in the tested estimates. Table 7 shows the values of the test statistics and the corresponding \(p\)-values. Among tested indicators, seven demonstrated statistically significant differences (T3, T4, T6, T7, T8, T10 and T12). These findings suggest that certain body regions are more sensitive to temperature changes caused by chair design or environmental factors. The most striking differences emerged in the back region (T7), which showed an exceptionally high value of test statistic (46.53). This pronounced variation likely stems from the fundamental difference between the mesh backrest designs (allowing greater airflow) and the foam backrest design in the LS model. The significantly higher test statistic value for this indicator suggests that the backrest material and design profoundly affect the thermal sensation at the back. Side-body thermal perception (T4) also demonstrated substantial variation, with a test statistic value of 23.39. This finding is particularly interesting because it relates to how the backrest design of the chair interfaces with the user's lateral body regions. This significant variation may reflect the differences in how each chair model constrains or facilitates airflow at the sides of the torso. Given the close proximity of this indicator, the subjects likely associated this feeling with warmth around the kidneys. Waist-level thermal sensation (T6) showed significant differences potentially reflecting the various backrest designs and their contact with the lower back region. Similarly, bottom thermal perception (T8) exhibited significant variation, likely influenced by the diverse seat constructions, from specialized anatomical designs (BS and IS) to technology-enhanced structures (LS and MA). Stomach thermal sensation (T3) also demonstrated significant differences, although to a lesser degree than the aforementioned regions. This variation might be related to the influence of different seat designs on posture, which in turn affects abdominal compression and the resulting thermal sensation. Torso back (T12) as a moisture indicator showed \begin{table}
\begin{tabular}{c c c c c c c c c c c c c c c c} \hline \hline  & **T1** & **T2** & **T3** & **T4** & **T5** & **T6** & **T7** & **T8** & **T9** & **T10** & **T11** & **T12** & **T13** & **T14** & **T15** \\ \hline Test stat. & 4.08 & 8.13 & 13.03 & 23.39 & 7.01 & 21.19 & 46.53 & 17.89 & 1.30 & 12.11 & 6.67 & 13.27 & 5.58 & 0.85 & 0.43 \\ \hline \(p\)-value & 0.54 & 0.15 & 0.02 \({}^{*}\) & 0.00 \({}^{*}\) & 0.22 & 0.00 \({}^{*}\) & 0.00 \({}^{*}\) & 0.00 \({}^{*}\) & 0.94 & 0.03 \({}^{*}\) & 0.25 & 0.02 \({}^{*}\) & 0.35 & 0.97 & 1.00 \\ \cline{2-13} df & 5 & 5 & 5 & 5 & 5 & 5 & 5 & 5 & 5 & 5 & 5 & 5 & 5 & 5 & 5 \\ \hline \hline \end{tabular}  
* Test stat. = test statistic; df = degree of freedom;
* = statistically significant differences at 5%.  
\end{table} 
Table 7: Kruskal-Wallis test results of differences between chairs. significant variations across the chair models. The torso back moisture sensation demonstrated greater variation, which aligns with the substantial differences observed in the back thermal perception (T7). This correlation suggests that the backrest design influences both temperature and moisture management, with a breathable mesh likely providing better moisture dissipation than foam.