Demographic Differences

• Nearly two-thirds of all adults living only with unrelated adult roommates (63.1%) were in households with only wireless telephones. This is the highest prevalence rate among the population subgroups examined.
• One-third of adults renting their home (33.6%) had only wireless telephones. Adults renting their home were more likely than adults owning their home (9.0%) to be living in households with only wireless telephones.
• More than one in three adults aged 25-29 years (35.7%) lived in households with only wireless telephones. Approximately 31% of adults aged 18-24 years lived in households with only wireless telephones.
• As age increased from 30 years, the percentage of adults living in households with only wireless telephones decreased: 19.1% for adults aged 30-44 years; 9.2% for adults aged 45-64 years; and 2.8% for adults aged 65 years and over.
• Men (18.0%) were more likely than women (14.4%) to be living in households with only wireless telephones.
• Adults living in poverty (26.0%) and adults living near poverty (22.6%) were more likely than higher income adults (14.2%) to be living in households with only wireless telephones.
• Adults living in the South (19.6%) and Midwest (17.8%) were more likely than adults living in the Northeast (9.8%) or West (13.7%) to be living in households with only wireless telephones.
• Non-Hispanic white adults (14.6%) were less likely than Hispanic adults (21.6%) or non-Hispanic black adults (18.5%) to be living in households with only wireless telephones.

Wireless-Mostly Households

Among households with both landline and cellular telephones, 22.7% received all or almost all calls on the cellular telephones, based on data for the period January through June 2008. These wireless-mostly households make up 13.3% of all households. These estimates are statistically similar to the estimates from the last 6 months of 2007.

• Adults with college degrees (17.1%) were more likely to be living in wireless-mostly households than were high school graduates (12.5%) or adults with less education (10.0%).
• Adults living with children (18.1%) were more likely than adults living alone (10.1%) or with only adult relatives (12.8%) to be living in wireless-mostly households.
• Adults living in poverty (10.8%) and adults living near poverty (10.3%) were less likely than higher income adults (17.1%) to be living in wireless-mostly households.
• Adults living in metropolitan areas (15.0%) were more likely to be living in wireless-mostly households than were adults living in more rural areas (12.1%).

Selected Health Measures by Household Telephone Status

• The prevalence of binge drinking (i.e., having five or more alcoholic drinks in 1 day during the past year) among wireless-only adults (37.7%) was twice as high as the prevalence among adults living in landline households (17.2%). Wireless-only adults were also more likely to be current smokers.
• Compared with adults living in landline households, wireless-only adults were more likely to report that their health status was excellent or very good, they were more likely to engage in regular leisure-time physical activity, and they were less likely to have ever been diagnosed with diabetes.
• The percentage without health insurance coverage at the time of the interview among wireless-only adults (28.3%) was twice as high as the percentage among adults living in landline households (13.6%).
• Compared with adults living in landline households, wireless-only adults were more likely to have experienced financial barriers to obtaining needed health care, and they were less likely to have a usual place to go for medical care. Wireless-only adults were also less likely to have received an influenza vaccination during the previous year.
• Wireless-only adults (49.3%) were more likely than adults living in landline households (35.8%) to have ever been tested for HIV, the virus that causes AIDS.

Conclusions

The potential for bias due to undercoverage remains a real and growing threat to surveys conducted only on landline telephones.

Citation:

Blumberg SJ, Luke JV. Wireless substi-tution: Early release of estimates from the National Health Interview Survey, January-June 2008. National Center for Health Statistics. Available from: http://www.cdc.gov/nchs/nhis.htm. December 17, 2008.