An institutional review board is the committee that must approve most human-subjects research before a single participant is enrolled. The approval exists to protect people from harm. It also routinely takes weeks to months, which changes what studies get run, who runs them, and when.
The delay is not an accident; it is the price of a system built after real abuses. But researchers, and the biotech and academic labs that depend on their work, pay that price unevenly. Understanding where the time goes explains a lot about why some promising studies never start at all.
This piece explains what an IRB actually does, how it judges a proposal, where the slowdowns come from, and how much of the current friction is inherent to the job versus added by scope creep.
What does an institutional review board actually do?
An institutional review board, or IRB, is a committee at a university, hospital, or company that reviews proposed research involving human subjects, then approves, requires changes to, or rejects it. Its central job is to make sure participants are not harmed, or that any harm is minimal and outweighed by the benefits of the research. As Wikipedia's overview of institutional review boards describes, boards conduct a kind of risk-benefit analysis of each protocol, checking that participation is informed and voluntary and that the risks to subjects are justified.
The review covers more than safety. IRBs examine the consent process, the fairness of how participants are selected, privacy protections for the data collected, and the plan for monitoring the study once it is running. Boards are typically made up of scientists, doctors, lawyers, and community members, so a protocol gets scrutinized from more than one angle.
IRBs are legally required in the United States for research that is federally funded, conducted by the federal government, or tests a product regulated by the FDA. The governing rules sit in Title 45 of the Code of Federal Regulations, Part 46, and the Office for Human Research Protections at the Department of Health and Human Services oversees the boards themselves. Many universities go further and review all human-subjects research, even that which falls outside the legal mandate. Readers following this should also see How does a federally funded lab discovery become a company?.
Why were IRBs created in the first place?
The system is a direct response to documented research abuses of the twentieth century. The most notorious was the Tuskegee Syphilis Study, in which the U.S. Public Health Service studied syphilis in Black men from 1932 to 1972 without treating them or even telling them what disease they had. The postwar Doctors' Trial of Nazi physicians and Cold War-era human radiation experiments added to the record.
Congress responded with the National Research Act of 1974, and in 1979 the federal government issued the Belmont Report. The report laid out three principles that still anchor review today: respect for persons, meaning informed consent; beneficence, meaning risks are weighed against benefits; and justice, meaning the burdens and benefits of research are shared fairly. IRBs became the local mechanism for enforcing those principles.
That history matters for the delay question. The waiting exists because the alternative, in living memory, was researchers experimenting on people without their knowledge. Any honest accounting of IRB friction starts from that baseline.
How does an IRB decide whether to approve a study?
When a researcher submits a protocol, the board checks it against criteria set out in the federal rules known as the Common Rule, first issued in 1991 and revised in 2018. According to a primer from payments company Tremendous, those criteria include minimal risk to subjects, risks reasonable in relation to anticipated benefits, informed consent that clearly communicates both, protections for vulnerable populations such as children and prisoners, and adequate safeguards for privacy and data confidentiality.
Not every study faces the full process. Research can qualify as exempt, which skips board review entirely, or go through an expedited review handled by one or a few reviewers. Full board review is reserved for riskier or more complicated protocols. Which track a study lands on is often the single biggest determinant of its timeline.
The board can also require modifications before approval, which starts a revision loop: the researcher responds, the reviewer re-reads, and the cycle repeats. Each round costs days to weeks. Studies that need multiple rounds of revisions can spend more time in review than in data collection.
Where do the delays come from?
Some delay is structural. A board meets on a schedule, often monthly or biweekly, so a submission that misses one cycle waits for the next. Reviewers serve part-time alongside their own research and clinical work. Complex protocols genuinely need careful reading. None of that is waste.
But the volume of what gets reviewed has grown. As the Good Science Project reported in April 2026, the Academic Freedom Alliance had recently issued guidance arguing that many boards now exercise authority over research posing no meaningful risk to participants, with simple surveys and even analyses of public records facing scrutiny similar to that applied to far riskier studies. Whether one accepts that framing fully, the underlying observation is widely shared: the share of reviewed research that involves minimal risk has risen over time.
There is even experimental evidence for a subtler version of the problem. Psychologist David Levari and colleagues asked participants to act as IRB reviewers, reading proposals and deciding whether to approve them. As the share of genuinely unethical proposals in the set decreased, reviewers did not reject fewer proposals. They started rejecting ethically ambiguous ones they would have approved earlier. The finding came from non-reviewers in a lab task, so it should be read as a suggestive model, not a measurement of real boards. Still, it offers a plausible mechanism: when bad cases get rarer, the threshold for what counts as a problem can drift downward.
Delay also compounds through the funding system. A grant year that loses three months to review is a grant year with three months less research in it. For graduate students and postdocs on fixed-term appointments, a stalled study can mean a stalled dissertation. For a biotech company, IRB timelines sit inside clinical development plans where each month has a carrying cost.
Can IRB review actually stop research, not just slow it?
Yes, and that is where the stakes get higher than scheduling. A board's disapproval is, in practice, final at that institution, and its authority extends to conditions on data and publication. Critics, including the former IRB chairs Jessica Hehman and Catherine Salmon as cited in the Good Science Project report, have documented cases where review processes appear to have been used to thwart research for ideological reasons or to protect an institution's reputation. We covered a connected angle in How U.S. science funding decisions actually get made.
The report's most detailed example involves memory researchers Elizabeth Loftus and Melvin Guyer, who in the late 1990s investigated a famous case they believed overstated proof of recovered traumatic memory, at the height of the debate over recovered memory therapy. Both were eventually cleared, but only after roughly three years of investigation that included the seizure of research materials, with a confidential memo from a university IRB chair later identified as a central element in the retaliation. The episode is contested and the source presents a critical account of it, but it illustrates the structural point: a body with gatekeeping power can be turned against researchers, not just for their protection.
Our analysis: the strongest case against IRB overreach is not that review is bad, but that review of trivially low-risk research consumes the same committee time that high-risk research needs. Every hour spent debating an anonymous survey of public records is an hour not spent on a protocol where consent and risk genuinely matter.
What this means for research timelines and the future of review
The evidence supports a layered conclusion. IRBs exist because of real, documented harm, and their core function, protecting volunteers in risky research, remains essential. The delays attached to that function are partly the honest cost of doing it well. What the reporting and the reviewer-behavior research both suggest is that the cost has been inflated by scope creep: more studies reviewed, more of them low-risk, with no clear gain in participant safety to show for it.
What remains unknown is the size of the effect. There is no reliable public figure for how much total research time IRB review consumes across U.S. institutions, and claims about suppressed studies rest on documented cases rather than a measured rate. Reform proposals, from broader exemption categories to risk-tiered review, aim to redirect board attention toward the studies that need it. Whether institutions adopt them is now the open question.
