The federal regulations under which IRBs operate do not clearly call for IRB review of the scientific validity of an investigator's research design. However, the federal regulations do require that IRBs determine whether "risks to subjects are reasonable in relation to...the importance of the knowledge that may reasonably be expected to result" [Federal Policy __.111(a)(2)]. "One of the ethical justifications for research involving human subjects is the social value of advancing scientific understanding and promoting human welfare by improving health care. But if a research study is so methodologically flawed that little or no reliable information will result, it is unethical to put subjects at risk or even to inconvenience them through participation in such a study.
In general, if an investigator is seeking funding from an external agency a study, the IRB leaves thorough scrutiny of the research design to the peer review process. The proposals of investigators who are not submitting to external agencies may be examined more closely for research design flaws, and they may be required to correct these flaws before IRB approval is granted.