Rigor and Reproducibility
Eight steps to Rigorous and Reproducible Experiments in Biomolecular Research at UNC:
- If using a core facility, consult with the core staff in the planning stage. Consult with a statistician if you need help developing a Power Analysis to assure that your results will be adequately powered.
- Design your experiment with sufficient controls (rigor) and replicates (reproducibility).
- Assure that ALL of your reagents (antibodies, cell lines, mice) are fully validated (see below).
- Have a clear and detailed protocol (SOP) and data analysis plan. Assure that the protocol is strictly followed or that any deviation is well documented.
- Assure that the staff or students performing the experiment are well trained and understand each step and the importance of performing them precisely.
- Use only well-maintained instrumentation, preferably maintained and operated in a core facility with expert staff (see #1 above).
- Document all steps, reagents, equipment and data analysis methods used in the experiment. Assure that the both the documentation and the data itself are properly stored in a safe data management repository.
- Acknowledge the Cancer Center Support Grant (P30 CA016086), the Animal Models Core, and appropriate Core staff in publications.
Guide to Rigor and Reproducibility for the UNC Animal Models Core and Studies Using Genetically Engineered Rodents
- Consult with the Core staff in the planning stage
- Ensure correct genotyping of transgenic animals
- Always include positive and negative controls in genotyping assays
- Understand the molecular details of genetic modifications in the strain and ensure genotyping strategies are appropriately designed to distinguish possible genotypes
- Be aware of possible genetic factors such as maternal or paternal germline recombinase expression that can produce unexpected genotypes
- Maintain a defined genetic background for your transgenic strains
- The Animal Models Core always provides new genetically modified strains on a defined genetic background. Ensure colonies are maintained on the original background unless introduction of a different background is experimentally dictated.
- Be aware that animals of the same strain from different vendors are not genetically identical and genetic differences between substrains can impact animal phenotypes.
- Be aware that intercrossing within a closed colony will lead to genetic drift over time. Colonies should be crossed back to wild-type animals from a genetically defined stock (e.g. vendor animals) at a minimum every 4 generations.
- Maintain complete breeding records to track genetic background in animal pedigrees.
- Include appropriate experimental controls
- The selection of appropriate controls depends upon the nature of the transgenic strain in use. In many cases littermate controls lacking the transgenic modification will be the ideal controls due to consistency of genetic background, pathogen status, microbiome, etc.
- Be aware of environmental variables that may influence experimental outcomes
- Variables such as type of feed used, pathogen exclusion status and microbiome can have a significant impact on experimental outcomes. Be aware of these conditions and ensure that experiments are designed to control for these variables.
- Ensure that all experiments involving animals are approved by the Institutional Animal Care and Use Committee (IACUC) and, where applicable, the Institutional Biosafety Committee (IBC).
Learn about the NIH Initiative to Enhance Reproducibility through Rigor and Transparency. (Video)
Resource Authentication Plan: https://grants.nih.gov/reproducibility/faqs.htm#V
What Kind of Information Should I Include in My Application’s Resource Authentication Plan? Check out instructions on NIH Nexus Blog.
What are ‘Key Biological and/or Chemical Resources’ that should be addressed your application’s authentication plan? Key biological and/or chemical resources include, but are not limited to, animal models, cell lines, specialty chemicals, antibodies and other biologics. More on NIH website
FASEB report on enhancing research reproducibility identifies three main gaps to research reproducibility:
- Lack of uniform definitions to describe the problem
- Insufficient reporting of key experimental details
- Gaps in scientific training