LACE Score: Readmission Risk Assessment
The LACE score is a validated 4-factor clinical tool that predicts a patient's risk of unplanned readmission or death within 30 days of hospital discharge, enabling targeted post-discharge intervention.
What is the LACE Score?
The LACE index was developed and validated by van Walraven et al. (2010) using data from 4,812 patients at two Ontario teaching hospitals. It predicts the risk of death or unplanned readmission within 30 days of discharge. The acronym stands for the four components that make up the score, which ranges from 0 to 19.
LACE Components
- L — Length of Stay (0–7 points): 1 day = 1 point; 2 days = 2; 3 days = 3; 4–6 days = 4; 7–13 days = 5; 14+ days = 7
- A — Acuity of Admission (3 points if emergent): Emergency/urgent admission scores 3; elective admission scores 0
- C — Comorbidities (0–5 points): Based on Charlson Comorbidity Index. Score 0 = 0 points; 1 = 1; 2 = 2; 3 = 3; 4 = 4; 5+ = 5 points
- E — Emergency Department visits in prior 6 months (0–4 points): 0 visits = 0; 1 = 1; 2 = 2; 3 = 3; 4+ = 4 points
Score Interpretation
- 0–4: Low risk
- 5–9: Moderate risk — consider post-discharge outreach
- 10–19: High risk — structured care coordination and early follow-up essential
Patients scoring ≥10 have an approximately 22% probability of readmission or death within 30 days. In the original validation cohort, high-risk patients (LACE ≥10) accounted for about 25% of patients but nearly 40% of readmissions.
Why LACE Matters for Analytics
LACE scores are most valuable when calculated automatically from EHR data at or before discharge, enabling care teams to prioritise high-risk patients for transitional care management (TCM), medication reconciliation, and 48–72-hour follow-up calls. Calculating LACE only on readmitted patients retroactively provides little operational value — the score must be prospective to trigger intervention.