​Todd Hughes is the director of the California Health Interview Survey (CHIS), the nation's largest state health survey, which released new 2015 data today. In this brief interview, Hughes discusses new topics, such as gender identity and telemedicine, and the role of cell phones and computers in CHIS data gathering.

Q: What new questions and innovations are in the 2015 CHIS?

​CHIS always tries to be responsive to the latest research questions and health challenges. Important new topics in the survey include whether Californians have experienced discrimination based on race or ethnicity ― allowing researchers and others to see for the first time whether bias is a factor in how people access and receive health care. We're also releasing new indicators on topics of emerging importance, such as telemedicine, which is receiving care from a doctor or health professional through a video or telephone conversation.

According to CHIS, 1 in 10 people used some form of telemedicine in 2015, a sizable percentage for such a new field and one that is likely to grow. In an era when it's hard for people to travel to a doctor, such as in rural areas with few providers or get an in-person appointment to see a doctor in a timely manner, telemedicine may be the only way some people get access to health care.

We're also releasing preliminary results of highly-anticipated data on adult gender identity and teen gender expression ― the first time we've ever collected these data. Even more data on these topics will be released in early 2017 when we publish an article on CHIS transgender data in the American Journal of Public Health in partnership with The Williams Institute at the UCLA School of Law.

As exciting as all our new topics are, CHIS is tremendously valuable for the many questions it asks again and again, allowing researchers to trend health and health care over time.

Q: How many indicators are being released by CHIS and why are some being held back?

​We are releasing more than 200 indicators with CHIS 2015 ― the most ever released at one time by CHIS. It's a big year! However, there are always questions that are held for later release. These are usually few and include open-ended question, like health insurance plan name, industry and occupation. We want to take special care and ensure we accurately capture the intent of the participant. Data for these additional questions will be released in early 2017.

Q: What proportion of respondents do you reach by cell phone? Will CHIS eventually move to an online survey?

​The design of CHIS has evolved to better reflect changes in the population and the increasing number of households that only have telephone service through mobile devices. In 2013-2014, we reached about 80 percent of respondents through land lines and 20 percent by cell phone. In 2015, we changed our sample design to contact roughly half of our survey respondents by cell phone.

Telephone surveys still allow us to reach a broad set of Californians, despite a changing culture with fewer people answering incoming phone calls. However, many surveys are moving to designs that involve asking people to respond by mail or Internet. These surveys may experience higher cooperation rates and can be conducted less expensively than telephone surveys, but there are some disadvantages as well. CHIS makes special efforts to conduct interviews in a large set of languages other than English to reflect California's diverse population, and this would be more challenging in a mail or Internet survey.

Someday, an approach that involves a blend of different approaches may make sense, and we will begin next year to examine these approaches in more detail.