From: Paradoxes in carcinogenesis: New opportunities for research directions
Question | Proposed experiment | Rationale |
---|---|---|
What aspect of the implant is responsible for sarcomas? | 2 × 2 × 2 × 2 factorial design involving surface area, roughness, electrostatic charge, pore size | A factorial design allows investigation of many factors at once. |
How does the implant affect cellular changes? | Primary study: no implant versus small pore implant that induces sarcoma | Looking for salient differences in gene expression using multiple random validation and signatures with few genes |
 | Secondary study: no implant versus large pore implant that does not induce sarcoma | Control study to determine if differences in gene expression could reliably be associated with histological changes |