A new study conducted by Centers for Disease Control and Prevention revealed that almost 15% of U.S. households depend on cell-only phone services with no backup landlines. The study was sponsored by the CDC's National Center for Health Statistics.

The study reported that about 14.7% of American households depend only on their cell phones. With 26.2 percent of households using cell phones as opposed to landlines, Oklahoma was leading in the country in the percentage of households with just cell phones, in 2007.

Commenting on the new findings, Stephen Blumberg, health scientist with CDC's National Center for Health Statistics said, "These findings are important to CDC because many of our larger surveys are done on calls to landline phone numbers. All of those adults with only cell phones are being missed in these surveys."

According to the study, the sates following Oklahoma in the percentage of households with just cell phones include Utah (25.5 percent), Nebraska (23.2 percent), Arkansas (22.6 percent), and Idaho (22.1 percent).

The study found that Oklahoma was also leading in the highest percentage of cell-only adults, with 25.1 percent of adults depending on cell phones only, and Delaware had the lowest population of adults using only cell phones, just 4 percent. The study also found that Washington, D.C. had the highest percentage of communities of cell-only users (25.4 percent).

According to the study, the percentage of cell-only phone user varies significantly within regions in the United States; for instance, the region wise highest population of cell-only users (23.2 percent) is in Nebraska, while South Dakota has the region's least number of cell-only users (6.4 percent).