Finding and Using Health Statistics
Surveys are an important means of collecting health and social science information from a sample of people in a standardized way to better understand a larger population. There are many methods used to conduct surveys, including questionnaires and in-depth interviews via phone, mail, email, and in-person.
Survey research allows researchers to collect empirical data in a relatively short period of time. Depending on the design and scope, surveys can collect data on a representative sample of people1, particularly when samples are randomized or purposive nonprobability sampling is used.
Survey research, like all research approaches, can have drawbacks. It can be hard to get detailed information in a survey, and sometimes people choose not to answer difficult questions, or they cannot remember important details correctly or at all (recall bias). Surveys can have low response rates, and those who do not have access to the medium through which the surveys are distributed are excluded. For example, homeless people may be excluded from a survey conducted via mail, and those without health insurance who cannot afford to see a doctor may be excluded from surveys conducted by health care providers.
When designing surveys, it is important to design questions carefully so that they are clear and understandable to the respondent, produce results relevant to the purpose of the survey, and are not a ‘leading’ questions, or questions that prompt a specific desired answer.
Information on a survey designed to collect health data might focus on patients, providers, or hospitals and doctor’s offices. Two major types of surveys are used to gather health statistics: population surveys and provider surveys. Below are selected surveys that the National Center for Health Statistics and other agencies provide. 2
- The National Health Interview Survey is an example of an interview-based population survey. Researchers interview people in their homes to learn about how they use health care, insurance, their access to care, and other topics.
- The National Health and Nutrition Examination Survey is another population survey. This survey covers topics like disease conditions, child growth and development; illnesses such as diabetes, hypertension, and cholesterol; and nutrition. This survey uses a mix of personal interviews, physical examinations, and lab tests.
- The National Ambulatory Medical Care Survey is a provider survey. To complete this survey, researchers interview physicians and visit medical centers to learn about patient demographics, diagnoses, provider specialties, and how they use electronic medical records.
This chart was created using data from the National Ambulatory Medical Care Survey3
This chart shows the number of physicians per population, the annual visit rate per population, and the annual visits per physician, by specialty within the United States from 1999-2000 and from 2009-2010. This information is likely gained from provider surveys.
A summary of current surveys and data collection systems under the purview of the National Center for Health Statistics (NCHS) can be found here. This page provides background information, such as data sources and methods, selected data items and topics, and targeted sample sizes, for surveys currently being conducted by NCHS.
The Department of Health and Human Services (HHS), along with the U.S. Census Bureau and various subsidiary agencies, conduct many other surveys and data collection activities, some of which are listed below. Explore their websites via the links on this page. For a detailed list of federal health-related surveys and data systems, visit: http://aspe.hhs.gov/sp/Surveys/index.shtml.
Medical Expenditure Panel Survey
National Survey of Family Growth
National Immunization Survey
Behavioral Risk Factor Surveillance System
National Survey of Children’s Health
National Home and Hospice Care Survey
Medicare Current Beneficiary Survey
1 Kelley, K., Clark, B., Brown V., and J. Sitzia. Good Practice in the Conduct and Reporting of Survey Research. International Journal for Quality in Health Care, 15 (3): 261-266. 2003.
2 Scheuren, Fritz. What is a Survey. American Statistical Association, 2004. //www.amstat.org/sections/srms/pamphlet.pdf
3 Hing E, Schappert SM. Generalist and specialty physicians: Supply and access, 2009–2010. NCHS data brief, no 105. Hyattsville, MD: National Center for Health Statistics. 2012.