Researchers have been warning for more than a decade that the United States was losing ground to its economic competitors abroad and would eventually fall behind them unless it provided more of its citizens with the high-level math, science and literacy skills necessary for the new economy.

Naysayers dismissed this as alarmist. But recent data showing American students and adults lagging behind their peers abroad in terms of important skills suggest that the long-predicted peril has arrived.

A particularly alarming report on working-age adults was published earlier this month by the Organization for Economic Cooperation and Development, a coalition of mainly developed nations. The research focused on people ages 16 to 65 in 24 countries. It dealt with three crucial areas: literacy — the ability to understand and respond to written material; numeracy — the ability to use numerical and mathematical concepts; and problem solving — the ability to interpret and analyze information using computers.

Americans were comparatively weak-to-poor in all three areas. In literacy, for example, about 12 percent of American adults scored at the highest levels, a smaller proportion than in Finland and Japan (about 22 percent). In addition, one in six Americans scored near the bottom in literacy, compared with 1 in 20 adults who scored at that level in Japan.