BEIJING, July 2  -- The Ministry of Education is tightening up a preferential policy that awards bonus points in the national college entrance exams, or gaokao, to students with exceptional ability in the sciences and sports, amid recent worries about abuse of the system.

The ministry is reducing the number of slots for such students and limiting the events that entitle them to the bonus points starting with this year's college admission period, according to a statement posted on its website on Monday.

"The new policy is meant to ensure the equity of college admissions by reducing the threat of fraud and abuse," said Chu Zhaohui, a senior researcher at the National Institute of Education.

Education analysts expect the amendment to help boost transparency, following a scandal involving the athletic achievement certificates of a group of students in Benxi, Liaoning province.

Eighty-seven out of more than 1,000 graduates from Benxi Senior Middle School who took the entrance exam in June had national-level athletics certificates that are good for 10 extra points, Xinhua News Agency reported.

Many viewed that number as suspiciously high - roughly equal to the total 89 certificates given to students in another five cities in Liaoning combined.

Twenty-five of the student athletes also received extra points for swimming skills even though their school didn't have swimming facilities.

Zhu Tiejun, director of the city's college admission office, confirmed with Xinhua that all the student athletes' certificates were legitimate. But the reassurance failed to assuage public concern over the issue.

"It's easy for some resourceful parents to help their children pass the certification tests organized by local sports authorities without too much supervision. I've long heard about it," said Yu Liuyang, a student who enrolled at Beijing Sport University with 10 extra points for basketball talent.

Under the ministry's latest amendment, the number of sports recognized for the bonus has been reduced to 17 this year from 70 previously. It accepts popular activities such as basketball, soccer and other athletics. Seventeen provinces will reduce the bonus points awarded from 20 points to 10 or below, while another eight jurisdictions will stop offering the extra points to student athletes altogether.

The preferential policy for winners of academic Olympiads, including math, physics, chemistry and biology, has also been amended.

Apart from students who are selected by the national Olympiad training team who will represent China in the international Olympiad, other winners at the national or regional level can no longer gain admission to college without taking the gaokao.

All provinces and regions across China also canceled extra points for regional winners. Seven provinces canceled extra points for national winners and 17 provinces reduced the extra points for national winners from 20 points to 10 or below.

The preferential policy was launched in 2000 to encourage students to develop their talents in both mind and body.

In 2010, the Ministry of Education also released a notice with several other ministries, requiring all provinces and regions to review and reduce the events that offer extra points to students with science or sports talent.

After the new policy took effect this year, the number of students taking advantage of extra points dropped from 50,000 to 30,000.

Xiong Bingqi, deputy director of the 21st Century Education Research Institute, said the policy is a positive move. But he expressed some concerns.

"It can reduce corruption related to the preferential policy and reverse the trend of more and more Chinese students studying to get the extra points. But what if students give up developing their talent after they realize that these skills can no longer bring them extra points and put them in a better place in the gaokao?

"Under such circumstances, a better solution is to set up a multi-evaluation system that enables colleges to enroll students not just on the basis of their performance in tests," he said.