Clinical Decision Support

Clinical Decision Support (CDS) is the set of real-time prompts and checks SystmOne surfaces during care. It is one of the most direct clinical-safety controls in the EMR — catching risks and omissions at the point of decision, before they reach the patient. This implementation supports ISO 9001 and ISO 27001.

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What CDS does in CCMS

Risk Alerts

Flags clinically significant findings as they are entered, for example:

• Narrow pulse pressure
• High blood pressure readings
• Overdue laboratory results

Condition-Specific

Context-aware popups tied to the presentation, for example:

• Pyrexia / febrile-symptom prompt
• Diabetes code prompt for NDR registration
• Protocol reminders for chronic disease

Completeness Checks

Guards against incomplete records:

• Mandatory fields before saving
• SNOMED-coded sections required
• Protocol logic that halts on missing key data

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Why it improves safety

Decision support at the point of care

CDS reduces reliance on memory and vigilance alone. By prompting at the moment of entry, it lowers the chance of a missed risk, an omitted field, or an un-coded diagnosis — the small gaps that compound into patient-safety incidents.

CDS works hand-in-hand with the other clinical-safety controls:

• Data validation & field restrictions — mandatory fields, dropdowns instead of free text, and protocol-based logic prevent incomplete or invalid records.
• Standardised templates — structured input with decision-support fields built in.
• Mandatory coding — SNOMED-CT codes must be entered before a record can be saved, keeping data clean and analysable.

Avoid alert fatigue

Decision support only helps if staff act on it. Too many low-value alerts cause alert fatigue, where important warnings are dismissed reflexively. Alerts should be reviewed periodically and tuned so that what fires is genuinely actionable.

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Examples of CDS in SystmOne

The prompts below are active in CCMS. Each is triggered by a clinical value or coded entry and surfaces an alert to prompt a specific action.

Narrow Pulse Pressure

Triggered when pulse pressure falls below 30 mmHg

Trigger

Systolic BP — Diastolic BP < 30 mmHg (e.g. 100/80 → PP = 20).

What fires

A red risk banner (non-modal) appears on the vital signs entry screen.

Why

Narrow PP indicates reduced stroke volume — seen in cardiac tamponade, aortic stenosis, heart failure, or significant hypovolaemia. Prompting early prevents deterioration.

Action expected

Review the patient; consider cardiac assessment, fluid status, or escalation. Document the clinical plan.

High Blood Pressure Readings

Triggered on repeated or severely elevated readings

Trigger

Systolic ≥ 180 mmHg or Diastolic ≥ 110 mmHg (single reading); or sustained elevation ≥ 140/90 across consecutive encounters.

What fires

A pop-up prompting the user to confirm the reading, re-check if appropriate, and consider a hypertension diagnosis code.

Why

Untreated or poorly controlled hypertension is a leading cause of cardiovascular morbidity. Early prompting supports diagnosis registration and timely treatment escalation.

Action expected

Confirm the reading (repeat if necessary). Apply Essential hypertension or escalate medication. Refer to Hypertension Protocol↴.

Pyrexia / Febrile Screening Prompt

Fever triggers a recommendation for infectious disease screening

Trigger

Temperature ≥ 38.0°C (100.4°F) recorded, or a coded entry of Pyrexia, Fever, or Febrile illness.

What fires

A condition-specific prompt asking whether infectious disease screening (e.g. dengue, leptospirosis, typhoid, COVID-19) is indicated based on the presentation.

Why

Fever is a common presentation for notifiable and infectious diseases. Early screening reduces diagnostic delay, supports outbreak detection, and ensures appropriate isolation.

Action expected

Assess for infectious causes, order relevant investigations (e.g. full blood count, dengue serology, blood culture), and apply the appropriate SNOMED CT code for the working diagnosis.

Allergic Warning

Prompts when a known allergen is encountered during prescribing or recording

Trigger

A coded allergy or adverse reaction is present on the patient record and a clinician attempts to record a drug, substance, or food from the same therapeutic or antigenic class.

What fires

A hard-stop alert (modal pop-up) displaying the allergen, reaction, severity, and date recorded. The user must acknowledge or override with a clinical reason before proceeding.

Why

Allergic reactions from penicillin, NSAIDs, and contrast media are among the most avoidable medication errors. An interruptive alert at the point of prescribing is the last line of defence.

Action expected

Review the allergy entry. If the drug is still clinically indicated, document the rationale (e.g. "penicillin skin test negative") and override. Otherwise, select an alternative.