The California Health Interview Survey (CHIS) today released new data based on interviews with more than 44,000 households in California. The survey, conducted by the UCLA Center for Health Policy Research, covered hundreds of topics affecting state residents' health and well-being.
Data on nearly 200 of these topics were released today on AskCHIS, the center's award-winning, free, easy-to-use Web tool that provides data by state, region, county and some service-planning areas in Los Angeles and San Diego counties. Even more data were released through free, downloadable public-use files from the CHIS website.
Additional data will be released through AskCHIS in the coming months.
The data represent a two-year (2011–12) effort to survey a representative sample of Californians in all 58 counties. CHIS is the largest state health survey in the nation and one of the few to provide robust samples of many typically underrepresented racial and ethnic groups.
Health care reform questions
The latest survey asked many questions that will be important in measuring the implementation of health care reform in California, among them:
- How many Californians are uninsured?
- Who is eligible to participate in Medi-Cal?
- Who is eligible to participate in Covered California, the state's new health insurance exchange?
- How many Californians are signing up for high-deductible health plans?
In addition, the 2011–12 survey asked new questions of Californians with individually-purchased insurance plans about how easy it was to secure coverage, the affordability of the plans they secured, and whether or not they received adequate assistance in getting coverage.
"CHIS will be an invaluable measurement tool in assessing the impact and success of health care reform implementation in California," said Ninez Ponce, the survey's principal investigator and a professor at the UCLA Fielding School of Public Health. "These data provide clarity on the first and largest state health care reform effort in the nation."
Aside from data on health care reform, CHIS 2011-12 features dozens of questions on important health topics, ranging from obesity, diabetes and access to care, to the health of elders and children and much more. The latest data include new questions on whether and how Californians use the Internet to seek health information, whether they are able to make an appointment with their provider in a timely manner, and, for teen respondents, whether their school situation is stable or they move from school to school, among other topics.
The survey also brings back some topics that have not been addressed in several iterations of the survey, including questions about stroke and arthritis that were last asked in 2005.
Conducted in five languages—English, Spanish, Chinese (Cantonese and Mandarin dialects), Korean and Vietnamese—the survey is one of the most diverse sources of health data in the world and is used by researchers as far away as Korea to examine the health of key ethic and racial groups. Of note, CHIS 2011–12 collected a particularly large amount of data on American Indians/Alaska Natives (AI/AN). These data will be especially valuable to AI/AN communities when linked with the decennial U.S. Census.
"CHIS tells stories that few other data sources can tell and does so at the local level, which is almost unheard of in other states," said David Grant, who directs the survey. "These data allow counties to truly take their pulse, as well as measure trends over time."
The survey is conducted by telephone, and the 2011–12 survey includes a much larger cell phone sample (over 20 percent) than previous cycles (6.4 percent in CHIS 2009).
CHIS provides data free of charge via AskCHIS or through public-use files available for download here (a one-time registration or login is required). Public-use files contain even more variables than those available on AskCHIS. In addition, access to even more—and confidential—CHIS data is available through the Center for Health Policy Research's Data Access Center (DAC). The DAC can also provide access to one-year samples of CHIS data.
CHIS is conducted by the UCLA Center for Health Policy Research in collaboration with the California Department of Public Health and the Department of Health Care Services and is supported by several public and private funders committed to improving the health of Californians.