# The Human-Centredness Metric: Early Assessment of the Quality of Human-Centred Design Activities
## 3 Results
### Assessment of Concepts
Meanwhile, the mean values for user experience (M_UserExperience) (Figure 6, yellow bars) for both the concepts without the additional use of methods (M0) and for those with the additional use of the Dialogue Principles (M3) reach comparatively low values in the fulfilment of the items, M \(\approx\) 3.2 (Table 1). Again, these descriptive statistics do not tell us anything about significance, but they do give us an indication of which items or groups of items are imprecise in their formulation or in the measured variables and therefore need to be optimised. Further analyses and measures to improve the items of the HCM will follow in Section 3.3; the question of significance will be examined in the following with the help of suitable sample tests. Regarding Hypothesis H0, the Friedman test [65] is applied, which is suitable for small, non-normally distributed samples as well as for connected samples. Since Hypothesis H0 was derived directly from the research question, not only the mean value of fulfilment across all items (M_HumanCentrendness) is compared here, but also the individual goals. As can be seen in Table 2, none of the tests fall below the significance value of \(p\) = 0.05, whereby the mean values of the usability and accessibility goals still show the greatest differences between the individual methods. The test statistic for the user experience shows a rather low value, X\({}^{2}\approx\) 2.6, while, for the avoidance of use-related damage, it shows no deviation at all, X\({}^{2}\approx\) 1.0. The statistical test cannot prove any significant changes through changes in the methodological support. Hypothesis H1 cannot be rejected and H0 cannot be accepted on the basis of this study. In addition, the effects of the participants themselves, the order of the experiments, and the product samples on the sum of all items is examined. Since the participants and the product examples are independent samples, we use the Kruskal-Wallis test [66]; the significance threshold value is always \(p\) = 0.05. With regard to the student participants and their possible heterogeneity, there are no significant differences between them (X\({}^{2}\)(3) = 1.346, \(p\) = 0.752). Hypothesis H2 can thus be rejected. With regard to the order in which the experiments were conducted, there were no significant differences between the concepts developed at the beginning and those developed at the end (X\({}^{2}\)(3) = 5.400, \(p\) = 0.145). For a more detailed investigation of possible learning effects, the achievement of the usability goal alone was also considered in relation to the \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Quality Goals** & **Total N** & **Test Statistic X\({}^{2}\)** &
\begin{tabular}{c} **Degree of** \\ **Freedom df** \\ \end{tabular} & **Asymptotic Sig. \(p\)** \\ \hline M\_HumanCentrendness & 4 & 3.900 & 3 & 0.272 \\ \hline M\_Usability & 4 & 6.474 & 3 & 0.091 \\ \hline M\_UserExperience & 4 & 2.605 & 3 & 0.457 \\ \hline M\_Accessibility & 4 & 4.500 & 3 & 0.212 \\ \hline M\_UseRelatedDamage & 4 & 1.000 & 3 & 0.801 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: [PERSON] test results on significance of fulfilment of human-centred design goals in dependence on the additional methods applied. sequence. Here, the change from experiment 1 to experiment 3 fell below the threshold value (\(X^{2}(3)=-2.375\), \(p=0.009\)); the change from experiment 1 to experiment 4, however, again showed no significance (\(X^{2}(3)=-0.875\), \(p=0.338\)). Hypothesis H3 is thus also rejected. In relation to the product examples used, again, no significant differences could be found with regard to the achievement of the human-centred design goals (\(X^{2}(3)=4.809\), \(p=0.109\)). Hypothesis H4 is also rejected. The calculation of the effect size due to lack of significance is waived.