An Institutional Review Board (IRB) is a formally designated committee established to review, approve, and monitor research involving human subjects. The primary purpose of this oversight is to protect the rights, welfare, and safety of participants. Every IRB ensures that risks are minimized and are reasonable in relation to any potential benefits of the research. This ethical review applies to a wide range of studies, including clinical trials, social science research, and behavioral studies. The necessity of this safeguard has led to the adoption of a centralized model to manage the growing complexity of modern research.
Defining the Central IRB
A Central IRB, often referred to as a single IRB (sIRB), is a single review body that assumes ethical oversight for multiple research sites conducting the same protocol. This structure is distinguished from a traditional local IRB, which is typically affiliated with a single institution, such as a hospital or university. Operating independently of any specific site, the Central IRB functions as the “IRB of record” for all participating locations in a multi-site study. This provides one consistent ethical review across the entire project. Many Central IRBs are independent, non-profit, or commercial organizations designed to standardize and expedite the review process for large-scale studies.
Functions and Responsibilities
The duties of a Central IRB are identical to those of any local IRB, maintaining the same high standards of human subject protection. Its primary function is the comprehensive review and approval of the initial research protocol, ensuring the study design is ethically and scientifically sound. This includes evaluating the risks and benefits to participants to confirm the risk is minimized and justified by the potential knowledge gained. The board also scrutinizes informed consent documents to ensure the language is clear, comprehensive, and fully explains the study’s purpose, procedures, risks, and benefits. Beyond the initial approval, the Central IRB performs continuing review, involving periodic checks of ongoing studies to monitor for new risks or safety information. The board must also review and approve any proposed changes to the protocol or consent form before implementation at any participating site.
Why Centralization is Necessary
The centralized model was developed to address the logistical challenges inherent in multi-site clinical trials, where the same study is conducted simultaneously at dozens of locations. Before centralization, each participating site’s local IRB conducted its own independent review, resulting in redundant ethical reviews of the exact same protocol. This duplication of effort caused significant administrative burdens, delays, and increased costs, slowing down the pace of medical discovery. Using a single Central IRB drastically increases efficiency by providing one consistent point of review and approval for all participating institutions. This streamlined approach allows trials to begin enrolling participants faster and accelerates the overall research timeline.
Regulatory Oversight and Requirements
Central IRBs operate within a legal and ethical framework established by federal regulatory bodies in the United States, such as the U.S. Food and Drug Administration (FDA) and the Office for Human Research Protections (OHRP). These agencies ensure that all IRBs comply with federal regulations, most notably the Common Rule (45 CFR 46 Subpart A), which provides the framework for ethical human subjects research. A foundational mechanism for the Central IRB model is the “reliance agreement,” formally known as an Institutional Authorization Agreement (IAA). This is a formal, written document where a local institution agrees to cede its ethical oversight responsibility for a specific study to the designated Central IRB. The revised Common Rule, effective after January 20, 2020, now requires the use of a single IRB for most federally-funded multi-site studies conducted domestically. While the Central IRB assumes responsibility for the ethical review of the protocol and informed consent, the local institution still maintains certain responsibilities. These include ensuring its researchers are qualified and managing any institutional conflicts of interest. Reliance agreements carefully outline this division of labor, ensuring all aspects of human subject protection are covered without unnecessary duplication.