Reporting Timelines and Where They Come From
Part of Principal Investigator (PI) Training: Safety Reporting and Unblinding.
About 4 minutes. Free, in your language, no account needed.
Why this matters
Almost every investigator has been taught that a serious adverse event must be reported to the sponsor within 24 hours. It is a useful working habit and it is not what ICH E6(R3) says. Knowing where each number actually comes from matters, because the source determines what applies to you, in your country, on this protocol.
What the guideline says
Section 2.7.2 sets out the investigator's safety reporting duties in four lettered points.
- (a) Adverse events and laboratory abnormalities identified in the protocol as critical to safety evaluations are reported to the sponsor according to the reporting requirements and within the time periods specified by the sponsor in the protocol.
- (b) Serious adverse events are reported immediately to the sponsor — immediately after the investigator reasonably becomes aware of the event — except for those the protocol or another document identifies as not needing immediate reporting.
- (c) Immediate reports are followed promptly by detailed written reports, and for reports of death the investigator supplies any additional information the sponsor or the IRB/IEC requests.
- (d) Safety reporting activities may be delegated, but responsibility for them remains with the investigator.
Note what is absent. There is no number of hours anywhere in that list. The guideline's word is immediately, qualified by after the investigator reasonably becomes aware.
Where the familiar numbers come from
| Number | Actual source | What it governs |
|---|---|---|
| 24 hours to report an SAE to the sponsor | The protocol or sponsor convention | Site to sponsor |
| 7 calendar days for fatal or life-threatening suspected unexpected serious adverse reactions | US regulation, 21 CFR 312.32 | Sponsor to FDA |
| 15 calendar days for other suspected unexpected serious adverse reactions | US regulation, 21 CFR 312.32; comparable clocks exist in other regions | Sponsor to authority |
Two practical consequences.
Your obligation is the protocol's. Read the safety section and find the actual number your protocol sets, because it is the one that binds you. Where the protocol says 24 hours, 24 hours is your rule — not because ICH says so, but because §2.7.2(a) points to the protocol and you signed it.
The 7 and 15 day clocks are mostly not yours. They are sponsor-to-authority obligations. But they run from the sponsor's awareness, which starts with your report — so a site that reports late compresses someone else's regulatory deadline. That is the real reason speed matters.
"Reasonably becomes aware"
The clock starts when you become aware, not when the event occurred. A participant hospitalized on Saturday and mentioned at Tuesday's visit generates awareness on Tuesday.
That makes awareness a process you can improve, and it is where sites actually lose time:
- A coordinator who learns of an admission and waits to tell the investigator until the next scheduled meeting.
- An external laboratory report that arrives in a queue nobody reads daily.
- A hospital discharge summary that reaches the site by post.
- Cover arrangements over a weekend that route to a voicemail.
Fix the awareness path and the reporting timeline mostly takes care of itself.
Two rules that prevent most late reports
Report on suspicion, not on certainty. The initial report does not require a diagnosis, a causality assessment or a complete picture. It requires the sponsor to know. Waiting for the discharge summary before making the initial report is the most common cause of a late one — and §2.7.2(c) exists precisely so that detail can follow.
Delegate the mechanics, not the duty. Section 2.7.2(d) is explicit. Your coordinator can complete and submit the form. The obligation is yours, which means you need a way of knowing it happened — a same-day confirmation to you, or a log you review weekly.
Key takeaways
- E6(R3) sets no 24-hour clock. §2.7.2(b) says immediately after the investigator reasonably becomes aware; the number in your protocol is the one that binds you.
- The 7-day and 15-day clocks are regional regulation governing sponsor-to-authority reporting, not your site's deadline.
- The clock starts at awareness, so the awareness path — weekends, external results, discharge summaries — is what to engineer.
- Report on suspicion and follow with detail (§2.7.2(c)); delegating the mechanics never delegates the duty (§2.7.2(d)).