Monitoring the impact of CAHPS® surveys on Star ratings

The Consumer Assessment of Healthcare Providers and Systems or CAHPS® surveys focus on critical aspects of patient care and act as an essential source of information on individual health care experiences. These surveys include questions regarding provider communication, patients' access to appointments and necessary care, ratings of health plans, and customer service interactions.

As health plans systematically gather data on patient experiences in outpatient and inpatient settings, insights are generated and compared across time, departments, and facilities. This initiative is part of a broader effort to enhance the delivery of safe, member specific care.With many Medicare Advantage (MA) plans seeing disappointing results in the newly released 2025 Star ratings, let’s break down how CAHPS scores factor into these results.

CAHPS scores and Star ratings

CAHPS measures can be made up of one answer to a survey question or a composite of up to six separate answers. Unlike other Star ratings measures, which are determined by rates and cut points, CAHPS survey answers create a mean score using complex statistical formulas. The number of stars assigned to CAHPS measures is determined by the following factors: 

1. Scores are grouped based on their distribution. The position of a contract's mean score is compared to all other contract scores for that measure using specific percentile cutoffs: 15th, 30th, 60th, and 80th. These base groups are defined by the current year's adjusted mean scores, where percentile cutoffs are rounded to the nearest whole number from zero to 100. Each group includes contracts with rounded scores that fall between the lower and upper limits of the cutoffs. 

2. The Centers for Medicare & Medicaid Services (CMS) uses statistical tests to determine if a contract's mean score is meaningfully higher or lower than the national average, or if any observed differences could have occurred randomly. If a contract’s average score is statistically significantly higher than the national average, it means the difference is unlikely to be due to chance. 

3. The statistical reliability of survey answers helps determine if a CAHPS score is trustworthy enough to be assigned a Star rating. This depends on the number of respondents, how varied the responses are within a contract, and how much contracts vary nationally on a scale from zero to one. A reliability score of greater than 0.70 is considered high. Low reliability scores are defined as those with at least 11 respondents, reliability of at least 0.60 but below 0.75, and in the lowest 12 percent of contracts ordered. A contract with a CAHPS score of <0.60 is considered very low reliability and does not receive a Star rating for that measure. 

4.The standard error (SE) is provided by CMS through a contract’s CAHPS vendor. When the SE of the mean score reliability is low, a contract can be assigned one star if its mean score is more than 1 SE below the 15th percentile. When a contract’s mean score is more than 1 SE above the 80th percentile with low reliability, they may receive 5 stars. 

How did CAHPS scores affect the 2025 Star ratings?

After the Star ratings are published, contracts that meet the percentile cutoffs for CAHPS surveys receive a rating. Based on the factors mentioned above, many contracts received a lower or higher Star rating than anticipated. Of the 13 percent of times a contract received a different Star rating than the cutoff indicated, 93 percent received a lower rating while only 7 percent received a higher rating. The Getting Appointments and Care Quickly base group cutoff increased by six points at every level. For example, the cutoff for a five-star rating increased from 80 to 86 between 2024 and 2025. The cutoffs for Care Coordination also increased across the board, while Getting Needed Care increased at the two-, three-, and four-star levels, indicating an increased focus on beneficiary care.

How can plans improve CAHPS scores?

To improve CAHPS scores, health plans need long-term strategies focused on enhancing member experiences. Key areas for improvement include:

1. Keep administration engaged: Health plan leaders should understand the importance of member experiences on performance and stay updated on CAHPS changes. New regulation changes require leadership support to secure resources to pivot quickly when changes come out and improve response rates.

2. Stay current on education and training: All plan and provider care teams that communicate directly with members should be informed about CAHPS and trained to appropriately address routine member concerns with the plan or provider. Every member touch is an opportunity to ask relevant questions to measure member experiences, helping ensure no opportunities for improvement are missed.

3. Move from intervention to implementation: Plans should regularly conduct mock surveys, using engagement tools such as Cotiviti’s Eliza, with members to gather proactive feedback throughout their health journeys from July to January. This gives plans time to address member areas of concern before the CAHPS blackout period.

4. Increase member responses: With new regulation changes, there are now many effective ways to communicate with members. Learn about your population and their preferred communication channels, communicate clearly, and meet members’ individual needs in the most convenient ways to increase member participation.

About the author

Thelma Belli is a Stars analyst supporting Cotiviti's Quality and Stars portfolio. Her primary responsibilities are to offer individualized support to our customers in reaching their Star Ratings goals through data validation, gap analysis, and results-driven interventions. CAHPS® is a registered trademark of the Agency for Healthcare Research and Quality (AHRQ).