Definition
The Serious Incident Framework (SIF) was the NHS's 2015 framework for investigating incidents that crossed a defined seriousness threshold, normally through a root cause analysis within 60 working days. PSIRF replaced it from August 2022, with the transition complete by autumn 2023, moving incident response from threshold-triggered investigation to planned, proportionate learning.
Source: NHS England, 2015 and August 2022 · Last reviewed 6 July 2026
The two frameworks side by side
| Aspect | Serious Incident Framework | PSIRF |
|---|---|---|
| Trigger | Incident crosses the "serious incident" threshold | Planned in advance in the organisation's PSIRP, plus a small set of national requirements |
| Method | Root cause analysis as the default | A range of learning responses, with the PSII reserved for the highest learning potential |
| Deadline | 60 working days | Agreed with those affected; investigations expected to average about three months |
| Analytical model | Linear cause and effect | Systems-based (SEIPS): people, tasks, tools and environment interacting |
| Engagement | Families informed of findings | Those affected involved from terms of reference onwards |
| Oversight | Commissioner sign-off of reports | ICBs oversee system effectiveness; no sign-off of individual reports |
The end of the serious incident threshold
Under the SIF, the pivotal question was categorical: is this a serious incident? Everything followed from that answer, which made the threshold itself the battleground. Declaring an incident meant a mandatory process; not declaring it meant, too often, no structured learning at all. PSIRF removes the category. There is no "serious incident" designation to argue over. Instead each organisation examines its own incident profile, decides where its response effort buys the most improvement, and writes that into a plan agreed with its integrated care board.
The exception is the short list of nationally required responses, most prominently deaths thought more likely than not due to problems in care, which always receive a PSII regardless of the plan.
From RCA to a range of responses
The root cause analysis is gone as the default instrument. In its place sits a toolkit: the after action review for contained events with an intact team, the swarm huddle for same-day learning, the multidisciplinary review for incidents crossing team boundaries, and the PSII where deep investigation is warranted. The change reflects a critique the framework makes openly: repeatedly producing RCA reports on similar incidents consumed investigative capacity without changing outcomes.
The analytical shift matters as much as the menu. SIF-era investigations traced a chain back to a root cause. PSIRF's methods treat incidents as products of interacting systems, so they look for the conditions that made the incident likely and the barriers that usually prevent it. Single root causes are treated as the exception rather than the goal.
Timescales and deadlines
The SIF's 60 working day deadline was its most visible discipline and its most routinely broken promise. PSIRF replaces it with timeframes agreed at the start with those affected, with the expectation that investigations average around three months and do not exceed six except in exceptional, agreed circumstances. Organisations lose the single number; families gain a date that was set with them and reflects the real scope of the work.
Oversight
Under the SIF, commissioners signed off investigation reports, which pushed effort into report quality rather than improvement. Under PSIRF, providers are explicitly not required to seek ICB sign-off for incident response reports. Integrated care boards instead oversee the strength of the provider's response system as a whole, and boards oversee whether safety actions actually reduced risk. The framework calls this supportive oversight, covered under the fourth aim. What that means for governance teams in practice is set out on the implementation page.