The "LACE index," a tool physicians and nurses often use to determine hospital patients' readmission risk, may have a blind spot, according to new research from Morgantown-based West Virginia University.
LACE stands for length of stay, acuity, comorbidity and emergency department (the four readmission risk factors the index considers). Patients who score higher in these four areas usually have an increased readmission risk.
But the researchers found the LACE index does not consider a key variable that may improve its predictions: whether patients are on Medicaid.
"LACE was validated and tested in Ontario, Canada," said researcher Jennifer Mallow, PhD, MSN. "The LACE index didn't look at things like payer because they have universal healthcare."
To evaluate the index's predictive value, the researchers compared patients' 30-day readmission rates to their LACE index scores, insurance status and functional issues such as illiteracy and substance misuse.
The only LACE variable that was linked to increased readmission rates was comorbidities, and the correlation was not very strong, the researchers found.
Additionally, LACE scores were typically higher for patients who did not return to the hospital, even though its design says the opposite.
The researchers found payer type had a significant relationship to readmission rates, and determining whether patients are on Medicaid could help providers better predict their readmission risk.
Including insurance status in the LACE index or more reliable measures of health disparities may help providers determine which patients have the highest risk of readmission, the researchers said.