Workers ages 50 to 54 are less confident about whether they will collect all of the Social Security and Medicare benefits they are being promised than are workers ages 55 to 64.

Researchers at Watson Wyatt Worldwide, Washington, are basing that conclusion on results from a 2007 survey of about 5,000 U.S. workers ages 50 and older.

Only 35% of workers ages 50 to 54 are confident or very confident about getting all of the Medicare benefits promised, for example, the researchers report.

The percentage of workers who are confident or very confident about Medicare benefits rises to 40% for workers ages 55 to 59, and to 49% for workers ages 60 to 64.

The percentage of workers who are confident about Social Security is 40% for the 50-54 age group; 50% for the 55-59 age group; and 62% for the 60-64 age group.