Clinical Decision Support (CDS)
Clinical Decision Support encompasses EHR-integrated tools that provide clinicians with evidence-based guidance — including alerts, order sets, and documentation templates — at the point of care to support clinical reasoning and reduce error.
What is Clinical Decision Support?
Clinical Decision Support (CDS) systems are tools embedded in or integrated with EHRs that provide clinicians with knowledge and patient-specific information, intelligently filtered and presented at appropriate times, to enhance health and healthcare delivery. CDS encompasses a wide range of tools: drug-drug and drug-allergy alerts, order sets, care plan templates, preventive care reminders, diagnostic support, and evidence-based dosing calculators. The Office of the National Coordinator for Health IT (ONC) recognises CDS as a key component of health IT-enabled quality improvement.
Alert Fatigue: The Central Problem
The clinical utility of CDS is severely limited by alert fatigue. Studies consistently show that clinicians override 49–96% of all CDS alerts. Drug-drug interaction (DDI) alerts — the most common CDS alert type — are overridden approximately 93% of the time. A 2017 JAMA Internal Medicine study found that each physician receives an average of 63 alerts per day. When nearly all alerts are ignored, clinically important alerts are missed at the same rate as trivial ones.
Specificity vs Sensitivity Tradeoff
Effective CDS design requires balancing sensitivity (catching all potentially important clinical situations) with specificity (only alerting when action is genuinely warranted). High-sensitivity, low-specificity CDS generates many false positive alerts, contributing to alert fatigue. High-specificity CDS alerts fewer physicians but the alerts that do fire are more actionable and less likely to be dismissed. The CDS 5 Rights framework — right information, to the right person, in the right format, through the right channel, at the right time in the workflow — provides a practical design standard.
How Analytics Differs from CDS
CDS operates at the point of care, interrupting the clinical workflow to influence individual decisions. Healthcare analytics operates outside the care encounter, providing population-level patterns, trends, and performance data that inform programme design, care management prioritisation, and quality improvement planning. Analytics can identify that a practice's PHQ-9 follow-up rate for positive screens is 34% (a programme-level problem) — something no point-of-care CDS alert can reveal or fix. Both tools are necessary but serve fundamentally different functions.