Scorecard Methods
The 2018 Scorecard on State Health System Performance, evaluates 43 performance indicators grouped into four dimensions:
- Access and Affordability (7 indicators):
includes rates of insurance coverage for children and adults, as well as individuals’ out-of-pocket expenses for health insurance and medical care, cost-related barriers to receiving care, and dental visits. - Prevention and Treatment (16 indicators):
includes measures of receiving preventive care and needed mental health care, as well as measures of quality in ambulatory, hospital, postacute, and long-term care settings. - Potentially Avoidable Hospital Use and Cost (10 indicators; including several measures reported separately for distinct age groups):
includes indicators of hospital and emergency department use that might be reduced with timely and effective care and follow-up care, as well as estimates of per-person spending among Medicare beneficiaries and working-age adults with employer-sponsored insurance. - Healthy Lives (10 indicators):
includes measures of premature death, health status, health risk behaviors including smoking and obesity, and tooth loss.
Disparity Dimension
The 2018 Scorecard evaluates performance differences within states associated with individuals’ income level for a subset of 19 indicators that span the other four dimensions of performance. For each state and indicator, we evaluate the difference in rates for the state’s low-income population (generally under 200% of the federal poverty level) and higher-income population (generally over 400% of the federal poverty level). States are ranked on the relative magnitude of the resulting disparities in performance. This method represents a change from that used in previous scorecard editions. Racial and ethnic disparities in state health system performance will be evaluated separately in a forthcoming report.
The following principles guided the development of the Scorecard:
Performance Metrics
The 43 metrics selected for this report span health care system performance, representing important dimensions and measurable aspects of care. Where possible, indicators align with those used in previous state scorecards. Several indicators used in previous versions of the scorecard have been dropped either because all states improved to the point where no meaningful variations existed (e.g., hospital quality process-of-care measures) or the data to construct the measures were no longer available. New indicators have been added to the scorecard series over time, ensuring the Scorecard reflects current and evolving priorities. See below for more detail on changes in indicators.
Measuring Change over Time
We were able to construct a time series for 37 indicators. Not all indicators could be trended over time because of changes in the underlying data or measure definitions.
There were generally two to three years between indicators’ baseline and current year data observation, though the starting and ending points depended on data availability. We chose this short time horizon to capture the immediate effects of changes relative to the policy and delivery system environment, such as recent coverage expansions under the Affordable Care Act, and other reforms as they are or may be enacted and implemented in the future.
We considered a change in an indicator’s value between the baseline and current year data points to be meaningful if it was at least one-half (0.5) of a standard deviation larger than the indictor’s combined distribution over the two time points — a common approach used in social science research.
To assess change over time in the Disparity dimension, we counted how often the within-state disparity narrowed, so long as there was also an improvement in observed rate for the state’s low-income population.
Data Sources
Indicators draw from publicly available data sources, including government-sponsored surveys, registries, publicly reported quality indicators, vital statistics, mortality data, and administrative databases. The most current data available were used in this report whenever possible. Appendix B provides detail on the data sources and time frames.
Scoring and Ranking Methods
For the 2018 Scorecard, we introduce a new method of ranking states based on a standardized measure of variation known as the “z-score.”
For each indicator, a state’s standardized z-score is calculated by subtracting the 51-state average (including the District of Columbia as if it were a state) from the state’s observed rate,and dividing by the standard deviation of all observed state rates. States’ standardized z-scores are averaged across all performance indicators within the performance dimension, and dimension scores are averaged into an overall score. Ranks are assigned based on the overall score. This approach gives each dimension equal weight, and within dimensions weights the indicators equally.
The z-score more precisely portrays differences in performance across states (as shown in Overall health system performance) than our prior simple ranking approach used in prior scorecards. It is also better suited to accommodate the different scales used across Scorecard indicators (e.g., percentages, dollars, and population-based rates). This method also aligns with methods used in Commonwealth Fund international health system ranking reports.
As in previous state scorecards, if historical data were not available for a particular indicator in the baseline period, the current year data point was used as a substitute, thus ensuring that ranks in each time period were based on the same number of indicators. Three indicators in the Avoidable Hospital Use and Cost dimension are stratified by age: preventable hospitalizations, 30-day readmissions, and avoidable emergency room visits. For these indicators, states’ z-scores are averaged across age groups into a single, measure-specific composite before determining the state’s dimension score.
Because of changes in indicators and methods, the 2018 Scorecard rankings are not comparable to those reported in previous scorecard reports.
Changes in Scorecard Indicators
The 2018 Scorecard includes several changes to the set of performance measures on which each state is evaluated. New performance indicators were added, including:
- two new measures of access to and use of mental health services by adults
- a new measure of employee contributions to the cost of their employer-sponsored health insurance costs
- several new quality and utilization measures to better capture the health care experience of working-age adults with employer-sponsored insurance:
- adult diabetics with an annual hemoglobin A1c test
- potentially inappropriate medical imaging for low-back pain
- potentially avoidable hospital admissions for ambulatory care–sensitive conditions
- potentially avoidable emergency department use for nonemergency conditions
- 30-day hospital readmissions.
We expanded our previously reported measure of suicide deaths to also include death from alcohol and drug use — collectively called “deaths of despair.”
Finally, we dropped several performance measures that no longer differentiated state-level performance or for methodological reasons, including:
- At-risk adults without a routine doctor visit in past two years
- Medicare beneficiaries with dementia, hip/pelvic fracture, or chronic renal failure who received a prescription drug that is contraindicated for that condition
- Medicare fee-for-service patients whose health provider always listens, explains, shows respect, and spends enough time with them
- Home health patients whose wounds improved or healed after an operation
- High-risk nursing home residents with pressure sores
- Years of potential life lost before age 75.
Additional information regarding the rationale for these changes is available upon request.