Health product development has been lately tainted by wariness in manufacturers, which has reduced trust in the system. It also affects Digital Health were patients' big data flows generated by numerous sensors are subject to increased security and confidentiality to lower the risks incurred. Our aim is to increase trust in the system again by implementing a dedicated Blockchain solution where data are automatically stored, and where each actor in the development process can access and host them. Blockchain has its downside, such as a subefficient management of big data flows. This study is a first step toward defining a Blockchain solution that will not deteriorate the Quality of Service in this particular context by using the Quality by Design approach. We will mainly focus on the time to consensus attribute which affects both of them. From our experiments' results generated after running screening design and surface response design on a practical Byzantine Fault Tolerance (pBFT) simulator, we find that the transmission time and the message processing time are the most impacting factors.