Experts Establish “Gold Standard” for Measuring Delirium Severity in Patients With Dementia

A new study from the Hinda and Arthur Marcus Institute for Aging Research and the University of Alabama at Birmingham provides strong evidence that a rigorous expert panel process can accurately and reliably measure delirium severity, even in patients with Alzheimer’s disease and related dementias, or ADRD.

The study, published in the Journal of Alzheimer’s Disease, establishes a “gold standard” for delirium assessment that could be used to evaluate future clinical tools. Delirium, a state of sudden confusion, is four to five times more common in people with dementia and is linked to faster cognitive decline and higher mortality.

“This rigorous process provides confidence that delirium severity can be rated accurately in patients with and without ADRD,” said Kenneth S. Boockvar, MD, director of the Division of Gerontology, Geriatrics, and Palliative Care at University of Alabama at Birmingham and lead author of the study.

“The multi-site prospective Better Assessment of Illness (BASIL) II study will develop and validate a new delirium severity instrument for use in patients with and without ADRD,” said Sharon K. Inouye, MD, MPH, director of the Aging Brain Center at the Marcus Institute and professor of medicine at Harvard Medical School.

There is currently no laboratory test or biomarker to diagnose delirium or track its severity. As a result, expert clinical judgment remains essential, particularly for complex patients with dementia. By validating an expert panel-based reference standard, this study provides a reliable benchmark against which new delirium severity tools can be tested.

The study assembled a panel of five experts in delirium and dementia, including specialists in geriatrics, cognitive neurology, geriatric psychiatry, and neuropsychology. Panelists independently reviewed standardized, single‑page case summaries and rated delirium severity before participating in structured consensus discussions for cases without initial agreement. This approach reflects best practices for complex clinical outcomes and is widely used in research involving complex geriatric conditions such as delirium.

The expert panel demonstrated strong reliability, achieving 80% agreement on delirium severity ratings during their initial independent reviews. Following structured group discussion, agreement increased substantially, reaching a Kappa score of 0.90. This indicates a close consensus. Instances of disagreement were most often associated with preexisting dementia, visual impairment, or residence in a nursing home.

The study evaluated 488 patients across a range of clinical settings, including medical wards, surgical units, and nursing homes, underscoring the broad relevance of the findings.

In addition to Boockvar and Inouye, the study’s multidisciplinary research team included Richard N. Jones, ScD, Warren Alpert Medical School at Brown University; Tamara G. Fong, MD, PhD, Marcus Institute and Beth Israel Deaconess Medical Center; Edward R. Marcantonio, MD, SM, Beth Israel Deaconess Medical Center; Catherine C. Price, PhD, University of Florida; Eran D. Metzger, MD, Hebrew SeniorLife, Beth Israel Deaconess Medical Center, and Harvard Medical School; Douglas Tommet, Brown University; Eva M. Schmitt, PhD, Marcus Institute; Cole Heine, ScB, Marcus Institute; and Mackenzie Topper, BS, Marcus Institute. 

This collaborative effort was conducted on behalf of the BASIL-II Study Group. The study was supported by the National Institute on Aging. 

About Hebrew SeniorLife
Hebrew SeniorLife, an affiliate of Harvard Medical School, is a national senior services leader uniquely dedicated to rethinking, researching, and redefining the possibilities of aging. Hebrew SeniorLife cares for more than 4,500 seniors a day across seven campuses throughout Greater Boston. Locations include: Hebrew Rehabilitation Center-Boston and Hebrew Rehabilitation Center-NewBridge in Dedham; NewBridge on the Charles, Dedham; Orchard Cove, Canton; Simon C. Fireman Community, Randolph; Center Communities of Brookline, Brookline; Jack Satter House, Revere; and Leyland Community, Dorchester. Founded in 1903, Hebrew SeniorLife also conducts influential research into aging at the Hinda and Arthur Marcus Institute for Aging Research, which has a portfolio of more than $87 million, making it one of the largest gerontological research facilities in the U.S. in a clinical setting. It also trains more than 500 geriatric care providers each year. For more information about Hebrew SeniorLife, follow us on our blog, Facebook, Instagram, and LinkedIn.