Russia, Hong Kong and Singapore shot to the top of 45 countries and provinces participating in a fourth-grade reading test, while England fell below the United States, according to results released yesterday.

Researchers attributed the gains of the top three on the 2006 test to changes in curriculum and teacher training, and to adding years of schooling. No. 1 Russia, which was bested by 13 countries and provinces in 2001, had the biggest increase in its score.

In England, which had the third-largest score decline on the Progress in International Reading Literacy Study, a top education official called on the public to "kick-start a new national debate about the value of reading," and said the government would spend $10 million distributing free books.

"This study shows that our highest-achieving children are reading less, with children's busy days leaving less time for books at home," the official, Ed Balls, the U.K.'s secretary of state for children, schools and families, said in a statement.

U.S. student scores dropped two points during the same period, which test coordinators said was not statistically significant. The performance of U.S. students came four years after enactment of the No Child Left Behind Act, which imposed new requirements on schools for reading improvement.

"Clearly, as the world becomes flatter, it's becoming more competitive," said U.S. Education Secretary Margaret Spellings in a statement. "We need to do better than simply keep pace."

England dropped to one notch below the U.S. Both countries were outscored by 13 others, including Luxembourg, Italy, Hungary, Bulgaria and Latvia.

Russia, Hong Kong and Singapore ranked near the middle of participating countries and provinces in 2001. Since then, Hong Kong and Singapore revamped their reading curriculums, instructional materials and teacher training, and Russia required students to begin school a year earlier.

The study involved a representative sample of fourth-graders in each country, 215,000 in all. The test had two 40- minute sections, one focused on literary reading and the other on informational reading. The questions included both multiple choice and open-ended questions requiring written responses.

Girls outscored boys in every country and province in 2006, a repeat of 2001, researchers said. Ina V.S. Mullis, co-director of PIRLS, which is based at Boston College, attributed the gap to girls' maturing earlier than boys and to reading material that is more appealing to girls.

The gap was particularly wide in Middle Eastern countries, she said.

Children in wealthier countries and provinces fared better on the test. Eight of the top 10 reading scores were achieved by countries or provinces with a gross national income per capita above $20,000 a year, with Russia and Hungary being the only exceptions.

South Africa had the lowest score, followed by Morocco and Kuwait.

Norway, which had the second-highest gross national income per capita, was in the bottom quartile of reading scores.