HEDIS Denominator and Numerator Analysis Case Study

Client question

A client wanted to understand competitor quality strategy in Medicare Advantage. The challenge was that MA plans often see HEDIS quality performance as aggregated rates, which makes it difficult to infer the underlying denominator size, numerator count, and improvement opportunity for each contract and measure.

Without denominators, the same percentage rate can mean very different things. A small denominator may be volatile, while a large denominator can signal a high-impact operational priority for Star Ratings strategy.

Data source

FastHSR used HEDIS individual-level files. The HEDIS Measures file is a person-level file that includes information about HEDIS measures for beneficiaries enrolled in each MA plan or contract during the year.

The file contains indicator variables for whether each beneficiary met the denominator and numerator requirements for each HEDIS measure. The contents of the data vary by measurement year and source of data. There was no HEDIS data submission requirement for the 2019 measurement year due to the COVID-19 pandemic.

Scope of work

• Process many years of HEDIS individual-level files.
• Identify MA contract ID and calendar year for each beneficiary-level record.
• Aggregate measure-specific denominator indicators by MA contract and year.
• Aggregate measure-specific numerator indicators by MA contract and year.
• Document year-specific measure availability and data-source variation.
• Deliver HEDIS denominators and numerators by MA contract ID and calendar year.

Why individual-level HEDIS data matters

Contract-level rates are useful, but individual-level HEDIS files make the measure math visible. For each measure, FastHSR could identify the eligible denominator population and the numerator population that satisfied the measure requirements.

This allowed the client to distinguish between contracts with similar rates but very different denominator sizes, to identify high-leverage measures, and to understand where competitor improvement efforts may have the greatest Star Ratings impact.

Measures supported

The delivered measure file included denominator and numerator counts across many HEDIS and Star Ratings-relevant measure families. Measure availability changed by year and source data, so FastHSR preserved calendar-year specificity in the output.

• Preventive screening measures.
• Diabetes and cardiovascular care measures.
• Medication adherence measures.
• Post-discharge and transitions-of-care measures.
• Respiratory, musculoskeletal, and chronic disease management measures.
• Measure-specific denominator and numerator indicator variables from the source files.

Competitive intelligence use cases

Denominators and numerators help quality strategy teams move beyond observed rates and estimate the scale of competitor opportunity. They also make it easier to evaluate whether a measure is likely to move a contract's Star Ratings performance enough to justify operational investment.

• Identify contracts with large denominator opportunity in specific HEDIS measures.
• Compare measure stability across contracts and years.
• Estimate the numerator improvement required to change performance.
• Track where competitors may be prioritizing quality-improvement resources.
• Support market-level Star Ratings strategy and quality-performance benchmarking.

Deliverables

• HEDIS denominators by MA contract ID and calendar year.
• HEDIS numerators by MA contract ID and calendar year.
• Multi-year measure availability documentation.
• Calendar-year handling that accounts for the lack of 2019 measurement-year HEDIS submission.
• Measure-level outputs suitable for competitive intelligence and Star Ratings strategy.

Frequently asked questions

Why are HEDIS denominators and numerators useful for Star Ratings strategy?

Aggregated HEDIS rates show performance, but denominators and numerators reveal measure size, opportunity, stability, and the scale of improvement required for MA contract strategy.

What are HEDIS individual-level files?

HEDIS individual-level files are person-level files that include indicator variables showing whether beneficiaries enrolled in each MA plan or contract met denominator and numerator requirements for HEDIS measures.

What output did FastHSR deliver?

FastHSR delivered HEDIS denominators and numerators by MA contract ID and calendar year across many years, with measure availability varying by measurement year and source data.

For HEDIS denominator and numerator analysis, Medicare Advantage quality analytics, Star Ratings strategy, or MA contract competitive intelligence, please email us.

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