Economic and environmental impact of reducing unnecessary coagulation screen testing on an acute medical unit: a...

Inappropriate coagulation testing contributes to inefficiency, cost, and environmental harm. Baseline audits on our acute medical unit (AMU) showed that one-third of coagulation screen requests lacked a clear clinical indication.

To reduce unnecessary coagulation screens on acute medical services [AMU and Medical Same Day Emergency Care (mSDEC)] by 90% within 12 months, aligned with National Health Service (NHS) Net Zero ambitions and our Trust's Green Plan.

Using the Model for Improvement, we conducted three Plan-Do-Study-Act cycles. Our analogue and digital interventions included revised triage order sets, condition-specific electronic order sets, and a digital decision prompt requiring clinicians to confirm test indication. Data were collected at baseline (January-February 2024) and re-audited after interventions (December 2024). Outcome measures were the proportion of inappropriate tests, cost savings, staff time, and carbon reduction.

At baseline, 34%-39% of coagulation screens were inappropriate across AMU areas. Postintervention, inappropriate testing reduced to 20% in mSDEC, 10% in AMU 1B, and 15% in AMU 1C. This equates to a projected annual reduction of 44 000 tests, saving £130 000, 367 staff hours, and 3.6 tonnes CO₂e (equivalent to a 9000-mile car journey). Laboratory workload and plastic waste also fell substantially.

Embedding decision prompts within electronic order systems achieved rapid, sustained reductions in unnecessary testing. This scalable, low-cost intervention aligns clinical practice with sustainability goals and offers a model for reducing unwarranted diagnostics across the NHS. In the face of the climate crisis, aligning practice with environmental goals is both a professional responsibility and an opportunity to improve care, efficiency, and outcomes. Key messages What is already known on this topic  Inappropriate coagulation testing is common across NHS acute care, with studies showing over one-third of tests lack a clinical indication.Excess diagnostic testing contributes to financial costs, staff workload, plastic waste, and carbon emissions.Previous quality improvement initiatives have focused mainly on education or guideline dissemination, with variable success. What this study adds  Embedding a simple digital decision prompt into electronic order sets significantly reduced inappropriate coagulation screens across an Acute Medical Unit.The intervention was low-cost, rapidly implemented, and co-designed with frontline clinicians to improve uptake and sustainability.Projected impact includes avoidance of 44 000 tests annually, saving ~£130 000, 367 staff hours, and 3.6 tonnes CO₂e, supporting NHS Net Zero targets.This scalable model demonstrates how small digital changes can drive large improvements in clinical quality, efficiency, and sustainability.