# The Human-Centredness Metric: Early Assessment of the Quality of Human-Centred Design Activities
## 5 Conclusions  
A research field as mixed as human-centred design needs applicable and reliable definitions and techniques to provide the basis for the comparability of its associated methods, on the one hand, and to estimate the fulfilment of human-centred design goals in product design at an early stage on the other hand. In this paper, we addressed the following research question: How can the human-centred idea be measured and evaluated based on resulting product concepts? As a first step and initial study to answer this question, we designed an empirical study applying the recommendations from ([PERSON] _et al._, 2016; [PERSON] _et al._, 2017) and following the design method validation models of ([PERSON] _et al._, 2016; [PERSON] _et al._, 2017), which primarily aimed to test the internal consistency, completeness, and applicability of the metric (HCM) developed to answer the research question. Regarding internal consistency, which, in the case of a metric, is a statement about how well the individual items measure the construct under investigation and no other, we were able to calculate a good Cronbach's alpha value, i.e., none of the items showed evidence of measuring a construct other than human-centredness. Regarding completeness, based on the items that showed no change due to variation in the independent variable and were marked as likely to be fulfilled for (almost)all concepts, there is a need to improve the formulations so that they better measure the addressed variables. In terms of applicability, we found limitations in the roughness of the initial design, especially for usability and user experience items. More detailed concepts or user descriptions would be necessary here. It is unclear to what extent the reformulation of the items could compensate for this limitation. As a second objective, this study also aimed to examine the extent to which the HCM is actually suitable for demonstrating the influence of an additional human-centred activity on the product design and thus examine the HCM's functionality. While the descriptive statistics and the graphical analysis showed certain tendencies suggesting improved human-centredness through the use of additional methods, the statistical analysis showed no significance in the results. The hypotheses about the impact of these methods could neither be conclusively confirmed nor rejected. Based on the success of human-centred methods in general, especially those with active user involvement, we assume that these methods fundamentally and undoubtedly have added value for the quality of human-system interaction and the user experience of products as a whole. This shall not be questioned here. However, we could not clearly prove or measure the strength of this effect for the three methods examined in this study. Only the potential of the HCM in evaluating human-centredness was presented and provided insights into the challenges and intricacies of measuring the strength of human-centredness in the early stages of product development. This study contributes to the ongoing discourse on the role of human-centred design in product development and highlights the importance of further research into effective methods of assessing and quantifying human-centredness. The questions that continue to await answers are therefore the following: How much user interaction is necessary in different development processes, or how much user-oriented work is too little to achieve added value for product design? How early can this effect be measured in the quality of the product concepts, or how early in the development process is too early for evidence? This contribution can be summarised as an initial study on the structure and applicability of a new metric for human-centredness evaluation. Further studies for the validation of the metric are thus needed. Future work should focus on applications with more concepts and fewer variables to ensure the increased internal validity of the study design.