Castlight’s Care Guides Cut ED Visits by Nearly 56% and Save $33.83 Per Member Monthly, Study Shows

Peer-reviewed analysis reveals the power of proactive navigation to improve outcomes and reduce costs

SEATTLE — September 23, 2025 — A peer-reviewed study published in IEEE Xplore reveals that Castlight Health Care Guides—human-led navigation embedded within its digital healthcare app—are a powerful lever for improving healthcare outcomes and reducing costs. Bypassing the traditional need for referrals or triggering events, care guides proactively connect users to high-value care, helping drive significant reductions in both monthly medical spending and avoidable emergency department (ED) visits, the study showed.

“The results speak for themselves: Care guides play a transformative role in digital health,” said Kertu Tenso, Ph.D., senior data scientist at apree health, the parent company of Castlight Health. “The ability for patients to have a personal navigator by their side when and where they need it underscores the importance of care guides as a frontline intervention. Smarter, earlier care decisions have a significant impact on cost and clinical outcomes.”

Key Findings

In an analysis of more than 20,000 individuals, researchers found:

• $33.83 average monthly reduction in healthcare spending per person over six months following their first interaction with the guide. This finding suggests that care guides support more efficient healthcare decision making, reducing unnecessary spending.
  
• 55.67% relative reduction in avoidable ED visits. This figure underscores how care guides can help users make timely, appropriate healthcare choices, directing patients to suitable care settings and preventing unnecessary ED visits.

Proactive Navigation via Castlight
Most traditional patient navigation services are triggered by a health event or intervention, such as a hospital admission, ED visit or enrollment in a disease management program. While showing promise in reducing inpatient care and ED use in high-need populations, this reactive approach often limits accessibility and may miss valuable opportunities for early intervention and prevention.

With its digital health app and human care guides, Castlight takes an on-demand, proactive approach to healthcare support. Users can engage with a care guide at any time—no referral needed—for assistance navigating benefits, finding high-quality providers and choosing the most appropriate, cost-effective care options.

Click here to learn more about the study—Connecting Digital Health to High-Value Care: A Quasi-Experimental Evaluation of the Impact of Care Guides with the Castlight App on Healthcare Costs and Utilization—and Castlight Care Guides.

Study Methodology
Castlight researchers compared 10,333 unique users of the Castlight app who engaged with care guides in 2023 with the same number of similar users who did not engage with them. To estimate how care guides affect healthcare spending and utilization, a quasi-experimental staggered differences-in-differences (DID) design was employed, controlling for time-varying factors and pre-existing differences between the groups to provide a more accurate assessment of care guides’ impact.

About Castlight Health
Castlight Health simplifies healthcare navigation by providing a comprehensive and highly tailored digital platform and clinical services. Leveraging advanced personalization capabilities, Castlight identifies individual needs to deliver customized health and wellbeing experiences, guiding individuals through their unique health journeys and helping them engage with the right programs and care at the right time. Founded in 2008, Castlight enables large employers and health plans to drive better outcomes, improve engagement and maximize the value of healthcare benefits. apree health, the parent company of Castlight Health, is a business unit of Mosaic Health. For more information, visit www.castlighthealth.com.