Fig. 1.

Organization of a research workflow by decomposition into building blocks amenable to verification. (A) Research pipelines are indicated by the gray arrows, whereas the orange blocks are the more specific building blocks necessary to execute the pipeline. A concatenation of research pipelines forms a research workflow. Each of the building blocks in this diagram can be verified by the challenges indicated by the black arrows emerging from the orange blocks. (B) Example of a research pipeline including the challenges discussed in Section 3. For the internal challenge example, levels of RNA extracted from tissue or cells are measured with 2 different technologies, one of which is used as reference. For the external challenge example, gene expression data from patients and control subjects are used to test whether a disease signature can be extracted and verified.