Ba et al FIGURE 1. Workflow of big data analysis. The workflow is a process that follows a certain direction (the orientation of arrow is important). 1-Scientific questions are the starting point to process big data analysis. 2-Preanalytical processes that include the recruitment, the collect, and the storage of data. The large amount of data potentially available warrants QC methods that ensure data integrity. 3-Downstream analysis processes and the right interpretation of the results, that is, which question can be answered with our results and possibly which application can be made. QC, quality control.