Measures to Identify and Track Racial Disparities in Childhood Asthma
Asthma Disparities Workgroup
Standards Subcommittee of the Asthma Disparities Workgroup
The Standards Subcommittee of the Asthma Disparities Workgroup is an interagency committee convened to address strategies in the Coordinated Federal Action Plan to Reduce Racial and Ethnic Asthma Disparities. The Plan was published in May 2012 under the auspices of the President’s Task Force on Environmental Health Risks and Safety Risks to Children
The Coordinated Federal Action Plan to Reduce Racial and Ethnic Asthma Disparities
The Coordinated Federal Action Plan to Reduce Racial and Ethnic Asthma Disparities (1) (the Plan) was released in May 2012 by an interagency Asthma Disparities Workgroup under the auspices of the President’s Task Force on Environmental Health Risks and Safety Risks to Children. The Plan provided four strategies for federal agencies to organize collaboration on actions to reduce the disproportionately high burden of asthma for minority children. Using input from stakeholders gathered at a December 2010 workshop, the strategies were based on consensus by the Asthma Disparities Workgroup on preventable factors contributing to disparities and effective interventions to address them. Participating federal agencies have been charged to collaborate in addressing the priority actions for each strategy.
A Strategy to Identify Children Impacted by Asthma Disparities
Each of the four strategies outlined in the Plan contain several priority actions for federal agencies and stakeholders to undertake in collaboration. A Standards Subcommittee of the Asthma Disparities Workgroup was convened to address Priority Action 3.2, “Standardize definitions, measures, outcomes and data/information collection methods, and maximize availability and use of collected data across federal asthma programs” in Strategy Three, “Improve capacity to identify the children most impacted by asthma disparities.” The Subcommittee consisted of staff from the Centers for Disease Control and Prevention (CDC), State Departments of Health (California, Minnesota, Rhode Island and Utah), the Health Resources and Services Administration (HRSA) and the National Institutes of Health (NIH, National Institute of Nursing Research) who had expertise in national and local asthma surveillance, analysis of survey data, epidemiologic research, and design and implementation of public health asthma interventions. Specifically, the Subcommittee effort focused on the first portion of the priority action to, “develop standards and apply standardization to… surveillance (health surveys, administrative data abstract)… and asthma program monitoring and evaluation.” The recommendations from the Subcommittee are also intended to address Priority Action 3.3, “Promote the use of standard definitions, measures, outcomes and information/data collection methods in state, local and community settings.” The overall goal of these priority actions is to improve comparability and comprehensiveness of information about the burden of asthma in disproportionately affected populations. Existing federal health surveys that have been the standard for asthma surveillance present an ideal resource to base standards for state and local level efforts to measure and track asthma disparities and to benchmark local patterns with national trends. Ultimately, increased collaboration, comparison, and data sharing will allow more accurate and timely estimation of disparities in multiple settings and across geographic levels.
Measuring disparities is complex, with conclusions easily impacted by value judgments and perspectives(2). The interpretation of disparities is complicated further when disparate data sources and measures are used. Valid comparisons require explicit identification of methods and measures so that the identification, characterization, and tracking of asthma burdens among populations at disproportionate risk can be optimized. These recommendations are based on established definitions of common measures used in analyzing asthma disparities in population- or intervention-based settings.
The Subcommittee identified 4 domains of measures used in surveillance of asthma risk and outcomes:
- Prevalence and outcome measures
- Risk factors
- Asthma management
- Asthma control
These domains were identified through a consensus-based review of national and state asthma surveillance efforts, national and state health survey content, and several additional resources (see “Resources” below) that focused on definitions, standardization, cataloging, and/or tracking of asthma-related measures.
The initial list of measures was evaluated to explore feasibility of measurement in multiple settings (e.g., ranging from state-based surveys to local asthma programs). The template for each measure was developed by adapting existing templates used for other federal initiatives that catalogued asthma and chronic disease measures(3,4). Templates for each measure address data- and measures-related issues based on consensus by subcommittee members and include the following:
- definition of each measure, including verbatim survey questions and related data collection information
- information on estimation/calculation of measures
- background on each measure to provide context for its significance to defining and understanding asthma burden
- specific information about how the measure contributes to understanding childhood asthma disparities
- limitations that could be encountered in collecting and/or estimating the measure
- related data resources that could provide additional context for using the standard
This effort is focused on children given that the mandate of the Coordinated Federal Action Plan concerns childhood asthma disparities. Most measures, however, are easily adapted to the adult population. For clarity of presentation, these adaptations are not explicitly included in this document.
The recommended measures included are not an exhaustive list, but those which have an established track record in national surveillance and/or program evaluation. There are certainly other measures and data sets that could supplement those presented in this document to provide a more detailed picture of challenges and disparities within a population of children. Additionally, there are no recommendations about which measures should be included in any study or evaluation. Those included in this document represent not a list of necessary measures, but those with the most robust definitions and available data that allow replication over time and in different settings. In addition, the current list of measures reflects current best practices. As efforts to improve measurement tools are underway, it is to be expected that current best practices will evolve and measures will change.
Other review considerations
One major concern in generating or comparing estimates is considering the “population at risk.” For this reason, recommendations for two types of rates are presented for some measures. A population-based rate is the number of persons with a given characteristic, such as a condition, divided by the total number of persons in the population. This type of measure provides information about the burden of the condition among the population, and is useful when considering questions such as whether sufficient resources exist to address the condition. Another type of rate is an at-risk rate, which is the number of persons with a given characteristic divided by the number of persons at risk for that characteristic. For example, for an at-risk asthma death rate, the denominator would not be the total population, but only persons with asthma which is the population at risk of dying from asthma. This type of rate is useful in that it adjusts for differences in the prevalence of the characteristic (e.g., asthma prevalence) between groups, and thus disparities reflect differences due to factors other than an underlying difference in characteristics between the groups being compared (see Appendix II in reference #5).
Recommendations are provided for different types of measures. One set includes measures of asthma prevalence and outcomes. For these types of measures (e.g., hospitalizations), definitions of counts, population-based rates, and at-risk rates are presented. Another group of measures describe aspects of quality of health care (e.g., receiving a flu vaccination) or extent of asthma symptoms (e.g., nighttime awakenings) which are primarily of interest only among the population of children who have asthma. For this reason, only at-risk rates are described for these measures. Other measures address characteristics that have been related to disparities in asthma related indicators. These disaggregation measures, such as race/ethnicity or insurance status, are used to categorize the population into subgroups. Asthma prevalence and outcomes and health care quality indicators are compared across categories of the disaggregation measures to assess disparities. Recommendations for these disaggregation measures (e.g., race/ethnicity, insurance status) describe definitions of categories.
The recommendations do not include information about age adjustment. Age adjustment is used to eliminate differences in outcome rates for population groups that result from differences in the groups’ age distributions. Among the pediatric population, however, the age span is limited, and thus differences in age distributions between groups is unlikely to contribute meaningfully to differences in outcome rates.
Resources and related efforts:
- Standardizing asthma outcomes in clinical research: report of the asthma outcomes workshop. J Allergy Clin Immunol 2012, 129(3), Supplement.
- Chronic Disease Indicators (https://www.cdc.gov/cdi/index.html), National Center for Chronic Disease Prevention and Health Promotion
- Social Determinants of Health: Know What Affects Health (https://www.cdc.gov/socialdeterminants/), Centers for Disease Control and Prevention
- Council of State and Territorial Epidemiologists
- 2010 Position Statement: proposed that CDC, CSTE and state partners develop data collection, analysis and dissemination capacity for asthma indicators
- 1998 Position Statement: established definitions for asthma surveillance
- The National Committee on Vital and Health Statistics recommended in a 6/22/2012 letter to the Secretary of the DHHS that DHHS undertake additional efforts in exploring the gaps in data collection and analysis for the measurement of SES on health surveys to improve population health and the efforts to reduce health disparities (http://www.ncvhs.hhs.gov/wp-content/uploads/2014/05/120622lt.pdf Cdc-pdf[PDF – 67 KB]External)
- Agency for Healthcare Research and Quality Measure Inventory (http://www.qualitymeasures.ahrq.gov/hhs/inventory.aspx#search=asthmaExternal)
- Healthy People 2020 (http://www.healthypeople.gov/External)
- National Surveillance of Asthma: United states, 2001-2010 (5)
(1) Coordinated federal action plan to reduce racial and ethnic asthma disparities. Washington, DC2012.
(2) Harper S, Lynch J. Methods for measuring cancer disparities : using data relevant to Healthy People 2010 cancer-related objectives. Washington, D.C.: National Cancer Institute; 2005.
(3) Busse WW, Morgan WJ, Taggart V, Togias A. Asthma outcomes workshop: overview. The Journal of allergy and clinical immunology. 2012;129(3 Suppl):S1-8.
(4) Centers for Disease Control and Prevention. Chronic Disease Indicators. https://www.cdc.gov/cdi/index.html. Updated January 15, 2015. 2015.
(5) Moorman JE, Akinbami LJ, Bailey CM, Zahran HS, King ME, Johnson CA, et al. National surveillance of asthma: United States, 2001-2010. Vital & health statistics Series 3, Analytical and epidemiological studies / [US Dept of Health and Human Services, Public Health Service, National Center for Health Statistics]. 2012(35):1-67.
Standards Subcommittee members:
Lara Akinbami, MD (co-chair), National Center for Health Statistics, Centers for Disease Control and Prevention
Cathy Bailey, MS, National Center for Environmental Health, Centers for Disease Control and Prevention
Wendy Brunner MS, PhD, Minnesota Department of Health
Paul Garbe, DVM, MPH (co-chair), National Center for Environmental Health, Centers for Disease Control and Prevention
Karen Huss, PhD, RN, NIH, National Institute of Nursing Research
Meredith Milet, MPH, California Department of Public Health
Meghan Towle, MPH, Rhode Island Asthma Control Program
Diane Pilkey, RN, MPH. Health Resources and Services Administration
Holly Uphold, PhD, Utah Department of Health
Hatice Zahran, MD, MPH, National Center for Environmental Health, Centers for Disease Control and Prevention