The Employee Benefit Research Institute asked enrollees in CDHC plans a series of questions to determine changes in cost-conscious behaviors. Surprisingly, with a few exceptions, there were no statistically significant differences between people who cost-conscious and those who were not. Enrollees who checked their health plan to see if a particular treatment or medication was covered, or who researched a doctor's quality rating before receiving services, had lower account balances than those who did not take such measures. Those who budgeted for health care expenses had higher account balances than those without a budget.

Asset levels in consumer-driven health plans are increasing, even while average account balances are leveling off, the report found. In 2009, CDHC plans held over $7 billion in approximately 5 million accounts. The average balance in 2009 was $1,419, a 5 percent increase from 2008; comparatively, balances increased 90 percent between 2006 and 2007.

The typical CDHC plan enrollee is young, unmarried, educated and moderately healthy, EBRI found. Enrollees are also likely to be higher-income than enrollees in traditional plans. Gender and whether enrollees had children don't appear to affect enrollment in CDHC plans. However, men do tend to have higher balances than women. They also rolled over more money in health savings accounts from one year to the next.

In August of 2009, men had an average $1,620 in an HSA or HRA, compared with women's average $1,366. EBRI attributes this difference in women's greater use of health care services compared to men. The difference gets smaller as accountholders age, and disappears for ages 45-54 and 55-64.

In 2009, just 10 percent of HSA accountholders didn't have a rollover. Over 3 million accountholders rolled over almost $4 billion in HSAs and HRAs. The average amount of a rollover was $1,295.

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