Open Nursing Core FHIR Implementation Guide (ONC-IG)
1.0.0 - release

Open Nursing Core FHIR Implementation Guide (ONC-IG) - Local Development build (v1.0.0) built by the FHIR (HL7® FHIR® Standard) Build Tools. See the Directory of published versions

Clinical Safety

Clinical Safety

The Open Nursing Core IG treats a defined set of validated assessment instruments as safety gates — structured checks whose purpose is to detect deterioration and risk early and to trigger a proportionate clinical response. This page describes those instruments, the computable logic behind them, and the clinical-safety governance context in which the IG should be implemented.

Clinical risk management context

Digital clinical systems used in the NHS are governed by two clinical-safety standards published by NHS England:

  • DCB0129 — clinical risk management for the manufacturer of a health IT system.
  • DCB0160 — clinical risk management for the organisation deploying it.

The ONC-IG is a specification, not a deployed product; it does not by itself discharge either duty. Organisations implementing these profiles SHOULD do so within their own DCB0160 clinical risk management process, with a nominated Clinical Safety Officer, a hazard log, and a clinical safety case. The safety-gate design of the IG is intended to support that process by making risk instruments explicit and computable.

Early warning: NEWS2

The National Early Warning Score 2 (NEWS2) is the NHS standard for detecting and responding to acute deterioration in adults. The IG models the full score and each of its component parameters:

Computable logic

Scoring is not left to manual calculation. The IG ships an executable Clinical Quality Language (CQL) library (ONC_NEWS2_Logic) that computes the score from the underlying FHIR observations, including the SpO2 Scale 2 logic used for patients with hypercapnic respiratory failure. This is paired with a ​NEWS2 Escalation PlanDefinition that encodes the response protocol.

Escalation thresholds

NEWS2 escalation follows the nationally defined bands:

NEWS2 result Clinical risk Response
0–4 Low Routine monitoring; ward-based review as needed
3 in any single parameter Low–medium Registered nurse review to decide if escalation is required
5–6 Medium Urgent review by a clinician competent to assess acutely ill patients
7 or more High Emergency response by a critical-care-capable team

Systems implementing this IG SHOULD automatically flag when a NEWS2 result crosses these thresholds, in line with the escalation PlanDefinition.

Pressure ulcer risk

Two complementary risk instruments are provided:

  • Braden Scale — assesses sensory perception, moisture, activity, mobility, nutrition, and friction/shear.
  • Waterlow Score — a UK-developed tool widely used across the NHS.

Pressure-area assessment must be read together with the Health Equity & Inclusion guidance: early tissue damage presents differently across skin tones, so a valid pressure-risk assessment depends on skin tone being recorded on the Monk Skin Tone Scale. This is the IG's fairness gate — a wound or pressure-area assessment is incomplete until skin tone has been captured.

Other safety instruments

  • MUST — Malnutrition Universal Screening Tool, for nutritional risk.
  • 4AT Delirium Screen — rapid screening for delirium in older or acutely unwell patients.
  • Morse Fall Scale — falls risk.
  • qSOFA — rapid identification of possible sepsis.

Conformance language

Throughout the IG, the key words MUST, SHOULD and MAY are used in the sense of RFC 2119. "MUST" denotes a requirement for conformance; "SHOULD" a strong recommendation that may be departed from with justification; "MAY" an option.

The instruments described here support clinical judgement; they do not replace it. Every score and escalation decision must be reviewed and actioned by a registered nurse or other competent clinician. Implementers are responsible for their own clinical safety case under DCB0160.