Capitol Correspondence - 10.14.19

Op-Ed: The Need for Stronger I/DD Data

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Members who have expressed the need for stronger data on individuals with intellectual / developmental disabilities (I/DD) might be interested in this opinion letter in The Hill, in which a scholar lays out ways existing data can be improved. Specifically, Dr. Susan Havercamp from the Ohio State University Nisonger Center writes:

“In the research community, concern is growing that those with intellectual and developmental disabilities are becoming invisible in data collected from nationwide health surveys. 

Regular collection, analysis and interpretation of health data is a crucial part of how the United States tackles public health. Data collected from health surveys informs planning, implementation and evaluation of public health practices which, in turn, affect researchers, policy makers, planners and IDD advocates in roles like ours at The Ohio State University Wexner Medical Center

This issue is not a new one. In 2002, a U.S. Surgeon General’s report called for improved data collection. The current methods of collecting that data, however, have left health organizations with a blind spot.


Just when resources were needed to help learn more about the IDD population, two major surveys cut items instead. The National Health Interview Survey and the Survey of Income and Program Participation, two major national surveys, no longer contain questions that allow for monitoring the health of people with IDD. 

Why can’t we get health information from the state developmental disability system? The truth is that only about one in five adults with IDD are known to the developmental disabilities services system in their states. States need accurate information to plan services to help the IDD population, yet the changes in national surveys make it impossible for many providers to get the data they need. 

Here are some of the changes needed to improve IDD representation in nationwide health data: 

Greater consistency in how IDD is defined

Across the community, a consensus on how to operationally define IDD is needed. Currently, there are a variety of different definitions of “developmental disabilities” that are used interchangeably. These differences are largely responsible for the variance in IDD prevalence rates reported in medical literature, and can leave a large portion of the population invisible to surveys.

Greater consistency in how people with IDD are identified and standardized methods for identifying people with IDD in large datasets will allow researchers to extract data across databases while ensuring individuals’ privacy. By establishing consistent IDD identifiers, the community will be able to address a broad range of research questions about the health of people with IDD. 


Continued collaboration

Collaboration across federal agencies and partnerships with the private sector will be essential to making adults with IDD more visible in health data. 

Efforts to improve health data have been highly collaborative, and included contributions from the Centers for Disease Control and Prevention, the administration on Intellectual and Developmental Disabilities and the National Institute on Disability and Rehabilitation Research. This collaboration concluded that items were needed to measure learning, independent living and age of onset to identify adults with IDD.

These collaborations are crucial to developing and maintaining a consistent survey question set to identify people with IDD in the National Health Interview Survey. Closer relationships between researchers, advocates and policy-makers can identify the most urgent research questions for analysis, capitalize on emerging technologies and determine directions for policy and programs. 

More sophisticated data analysis

In addition to improved IDD data it’s important for the health-care community to make better use of the data currently available. 

Much of our analytic expertise is concentrated among a relatively small group of researchers with the capacity to analyze data in ways that inform policy-makers to support decisions informed by quality data. 

As we increase policy makers’ interest and understanding of people with IDD, more extensive and more distributed expertise is needed. For example, a positive change would be the addition of analysts at the state or national level who can combine data sets across agencies and use sophisticated modeling techniques to determine how best to interpret data. 

Diversity representation

Data collection and analyses need to routinely examine race, ethnicity and other characteristics that are known to contribute to marginalization and health disparities in society. 

Today, there are few efforts to understand how the health-care barriers faced by people with disabilities are compounded by race or ethnicity. A 2014 review found that only 1 in 73 published studies were specifically designed to examine barriers to health-care access for people with disabilities who are also members of underserved racial or ethnic groups.

Race and ethnicity are critically important in understanding health of persons with IDD, and studies have found striking disparities across racial and ethnic groups. Often, innovative health technologies are not equally available to groups marginalized by race, ethnicity or poverty.

In the two decades since the surgeon general’s call for better data, we have learned a great deal about how and what to measure to understand and improve the health of people with IDD. 

But more work needs to be done, and we look forward to progress in the coming decades that will result in people with IDD becoming fully visible and valued.”

Dr. Susan Havercamp is director of the Health Promotion and Healthcare Parity Program at the Ohio State University Nisonger Center. She is a consulting editor for Intellectual and Developmental Disabilities and Inclusion and the book review editor for the Journal on Mental Health Research in Intellectual Disabilities.