Health survey dilemma: Can you hear me now?

With cell phones replacing landlines, researchers seek to ensure that the answers they get are accurate when they ask about health behaviors.

By Susan J. Landers, AMNews staff. Oct. 15, 2007.

Washington -- As more Americans ditch their traditional home telephones in favor of cell phones, researchers who keep tabs on the nation's health via telephone are becoming increasingly concerned that important segments of the population are being missed.

For the first time, bias threatens surveillance systems used by state and local health departments to establish policies on an enormous range of health behaviors, from alcohol use and smoking to diabetes awareness and who's getting a flu shot. The fear is that population-wide interventions could be off-target, and even physicians' understanding of patients' health risks may be somewhat askew.

Many telephone surveillance systems -- including the world's largest, the Behavioral Risk Factor Surveillance System, which was established in 1984 by the Centers for Disease Control and Prevention and state health departments -- traditionally have collected data by landline phones. Now, sizeable chunks of the population have chosen to become entirely wireless, making it much more difficult -- and expensive -- to reach them.

Data from the 2006 National Center for Health Statistics' National Health Interview Survey, which is conducted in person, indicate that 25% of 18- to 29-year-olds and 32% of low-income young adults live in households with only wireless telephones.

The number of cell-only users rises to nearly a third among young adults ages 25 to 29, said Mike Battaglia, a vice president at Abt Associates, a research consulting firm in Cambridge, Mass.